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Abstract

We compare homicide rates in two quite similar cities with vastly different execution risks. Singapore had an execution rate close to one per million per year until an explosive 20-fold increase in 1994–1995 and 1996 to a level that we show was probably the highest in the world. Then, over the next 11 years, Singapore executions dropped by about 95 percent. Hong Kong, by contrast, had no executions at all during the last generation and abolished capital punishment in 1993. Homicide levels and trends are remarkably similar in these two cities over the 35 years after 1973, with neither the surge in Singapore executions nor the more recent steep drop producing any differential impact. By comparing two closely matched places with huge contrasts in actual execution but no differences in homicide trends, we have generated a unique test of the exuberant claims of deterrence that have been produced over the past decade in the United States.

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... The fact that the most serious criminals were not deterred by the risk of added jail time in the Italian experiment, and the less serious criminals were deterred, shows that as one marches down the path toward more serious criminal propensities (or toward adolescence, as Lee and McCrary [2009] show), the evidence of deterrence weakens or vanishes. A final noteworthy study by Zimring, Fagan, and Johnson (in press) that compares the nearidentical murder paths of Singapore and Hong Kong despite the latter's renunciation of capital punishment and the former's wildly enthusiastic embrace of it provides yet another indication that Kovandzic et al. (2009) have it right when they conclude that the death penalty has no net deterrent effect in the postmoratorium United States (Zimring et al., 2009). ...
... The Zimring et al. (2009) piece is so powerful because Singapore made Texas look like a piker when it came to using the death penalty; yet the matched-comparison state of Hong Kong experienced the same time path of murder while jettisoning capital punishment. Perhaps someone will show that Singapore's massive jump in executions and subsequent massive decline were tightly calibrated to keep the murder rate moving along a similar path to Hong Kong, or that Hong Kong had some unusually good crime experience when things were going south in Singapore, but the likely answer is what we see from the Italian experience-the most serious criminals are not particularly responsive to threats of higher severity, whether they be a longer sentence or capital punishment. ...
... From such combined evidence, a pattern is beginning to emerge that the most serious criminals (and juvenile-offending adolescents) simply are not susceptible to distant threats of heightened punishment, perhaps because they fear they will not be caught, they never think about the consequences of their impulsive acts, or they just do not care. I will be interested to hear if Berk is moved by the Zimring et al. (2009) article to conclude that massive increases in the use of capital punishment followed by an elimination of the death penalty had no discernible effect on murder in Singapore. I would take the Singapore experience as credible evidence effectively ruling out a deterrent effect of even heavy reliance on executions-at least in Singapore when carried out in the (rather odd) Singaporean way. ...
... The fact that the most serious criminals were not deterred by the risk of added jail time in the Italian experiment, and the less serious criminals were deterred, shows that as one marches down the path toward more serious criminal propensities (or toward adolescence, as Lee and McCrary [2009] show), the evidence of deterrence weakens or vanishes. A final noteworthy study by Zimring, Fagan, and Johnson (in press) that compares the nearidentical murder paths of Singapore and Hong Kong despite the latter's renunciation of capital punishment and the former's wildly enthusiastic embrace of it provides yet another indication that Kovandzic et al. (2009) have it right when they conclude that the death penalty has no net deterrent effect in the postmoratorium United States (Zimring et al., 2009). The Zimring et al. (2009) piece is so powerful because Singapore made Texas look like a piker when it came to using the death penalty; yet the matched-comparison state of Hong Kong experienced the same time path of murder while jettisoning capital punishment. ...
... A final noteworthy study by Zimring, Fagan, and Johnson (in press) that compares the nearidentical murder paths of Singapore and Hong Kong despite the latter's renunciation of capital punishment and the former's wildly enthusiastic embrace of it provides yet another indication that Kovandzic et al. (2009) have it right when they conclude that the death penalty has no net deterrent effect in the postmoratorium United States (Zimring et al., 2009). The Zimring et al. (2009) piece is so powerful because Singapore made Texas look like a piker when it came to using the death penalty; yet the matched-comparison state of Hong Kong experienced the same time path of murder while jettisoning capital punishment. Perhaps someone will show that Singapore's massive jump in executions and subsequent massive decline were tightly calibrated to keep the murder rate moving along a similar path to Hong Kong, or that Hong Kong had some unusually good crime experience when things were going south in Singapore, but the likely answer is what we see from the Italian experience—the most serious criminals are not particularly responsive to threats of higher severity, whether they be a longer sentence or capital punishment. ...
... From such combined evidence, a pattern is beginning to emerge that the most serious criminals (and juvenile-offending adolescents) simply are not susceptible to distant threats of heightened punishment, perhaps because they fear they will not be caught, they never think about the consequences of their impulsive acts, or they just do not care. I will be interested to hear if Berk is moved by the Zimring et al. (2009) ...
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In 1975, Isaac Ehrlich launched the modern econometric evaluation of the impact of the death penalty on the prevalence of murder with a controversial paper that concluded that each execution would lead to eight fewer homicides. A year later, the Supreme Court cited Ehrlich's work in issuing an opinion ending the execution moratorium that had started with the 1972 decision in Furman v. Georgia. The court held that capital punishment could satisfy constitutional requirements if it was administered in accordance with more elaborate capital sentencing procedures as a punishment for only the most egregious, highly aggravated murders.
... On the other hand, empirical studies such as the one by Zimring et al. (2010) demonstrate that there is no proof of the death penalty's effectiveness as a deterrent in Singapore. More studies are needed in the local context, particularly the death penalty's effectiveness as compared to other punishments such as long-term imprisonment. ...
... The judge put the burden of proof of the inadequacy of life imprisonment squarely on the Prosecution. As is well known in the literature, there is no compelling evidence of the deterrent effect of the death penalty (Berk 2005;Cohen-Cole et al. 2009;Zimring et al. 2010;Hood and Hoyle 2015). 46 Unfortunately, PP v Wang Wenfeng (2014) is only a Singapore High Court 43 Pao-Keerthi (2014) suggest that the following considerations may be relevant: (1) existence of similar antecedents and (2) amount of drugs involved. ...
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Singapore is one of the few countries in the world which still imposes the death penalty for certain criminal offences. Until recently, it was the mandatory sentence for murder, drug trafficking and use of firearms—and it is these three offences which comprise nearly all of the executions in Singapore. This article examines the use, historical origins and recent legislative and judicial developments in the death penalty in Singapore. While the number of executions has fallen to very low levels in recent years and changes to the law relating to the mandatory death penalty in murder and drug offences have been made, it is the opinion of the author that the death penalty will continue to be used in Singapore in the foreseeable future.
... Our main finding for Japan is consistent with the findings from studies that have been done about the death penalty and homicide deterrence in the United States, which ''do not establish a deterrent effect of the death penalty'' (Sunstein and Wolfers, 2008). Our finding for Japan is also consistent with findings from recent peer-reviewed studies of the death penalty and deterrence in Singapore ( Zimring et al., 2010) and Trinidad and Tobago (Greenberg and Agozino, 2011) and with findings from previous studies of criminal deterrence in Japan ( Matsumura and Takeuchi, 1990;Mori, 2016;Sakamoto et al., 2001). There might be good reasons to challenge our conclusion that the death penalty does not deter homicide or robbery-homicide in Japan, but inconsistency with the results of previous research is not one of them. ...
... Although these surveys have serious methodological flaws, the available evidence suggests strong public support for the death penalty in Japan (Sato, 2014). 2. Studies of the death penalty and deterrence outside the United States include Adeyemi (1987), Zimring et al. (2010), Chen (2011), Greenberg and Agozino (2011), and Amnesty International (2013). ...
Article
Japanese officials commonly claim that their country retains and uses capital punishment because it deters homicide. Although this claim is contested, few empirical studies have been done to assess the empirical reality. This paper uses data not previously available (monthly homicide statistics obtained from Japan’s National Police Agency) to examine whether Japan’s death penalty deters homicide or robbery-homicide. Using vector autoregression models, it concludes that neither death sentences nor executions deter homicide or robbery-homicide.
... Founded by the British in 1848, modern Singapore became self-governing as a territory of the British Empire in 1959, and joined Malaya, Sabah and Sarawak to form the Federation of Malaysia within the British Commonwealth in 1963. In 1965 Singapore acquired independence from Malaysia following a period of terrorism and social unrest (Zimring et al., 2010: 3). Moving " from the third world to first " , as Lee put it (2000), Singapore emerged as one of the world's leading financial centers in the 1980s. ...
Article
The consensus over independent constitutional judicial review – that it inevitably stems from electoral and inter-branch competition – has been weakened by recent empirical discoveries; however, empiricists have yet to offer a coherent explanation why non-competitive, authoritarian, governments would tolerate constitutional courts that strike down their legislation. This article proposes a “Constitutional Investment Theory†that solves this puzzle: expressive symbolism is central to these regimes’ calculus for acquiescing in the activation of judicial review; the variable perdurability of judicial review depends on how much trust the regime invest in the judiciary; and activism in judicial review is the likelier to emerge the higher the transaction costs of retaliating against offending courts. Evidence from Singapore and pre-2000 Taiwan lends support to this theory.
... The problem of trying to assess the influence of a particular statutory change by looking before and after its enactment is obviously not limited to the assessment of drug law reform. A conventional method used to test the deterrent effect of capital punishment, for example, involves comparing the rates of homicide before and after state abolition (Zimring, Fagan, and Johnson 2010). But most countries and states formally abolish the death penalty only after years of de facto moratoriums. ...
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In 2001, Portugal decriminalized the acquisition, possession, and use of small quantities of all psychoactive drugs. The significance of this legislation has been misunderstood. Decriminalization did not trigger dramatic changes in drug-related behavior because, as an analysis of Portugal's predecriminalization laws and practices reveals, the reforms were more modest than suggested by the media attention they received. Portugal illustrates the shortcomings of before-and-after analysis because, as is often the case, the de jure legal change largely codified de facto practices. In the years before the law's passage, less than 1 percent of those incarcerated for a drug offense had been convicted of use. Surprisingly, the change in law regarding use appears associated with a marked reduction in drug trafficker sanctioning. While the number of arrests for trafficking changed little, the number of individuals convicted and imprisoned for trafficking since 2001 has fallen nearly 50 percent.
... The study focused only on the impact of abolishing the death penalty, without examining the effect of changing levels of death sentencing or executions on crime. Zimring, Fagan and Johnson (2010) compare homicides in Singapore (a country that has capital punishment) with homicides in Hong Kong, which does not. Though their work does what it can with the limited quantitative data available for these two places, it, too, is unable to examine the impact of changing levels of sanctions on homicides, for lack of data. 1 ...
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The effect of death sentences, executions and imprisonment on crime rates in the Republic of Trinidad and Tobago is assessed using annual time series data from 1955 to 2005. Policy implications of the research findings are drawn, and speculations are offered as to the reasons for the recent large increase in homicide rates.
... All top empirical academics should recognize that the Gius study on assault weapons as well as the studies by Ehrlich or Adler and Summers on the death penalty are not worthy of credence, but I have already alluded to the disputes over far more solid empirical work that is still rejected by purists who are unwilling to see any value in empirical studies that are not in category 2 or above (that is, randomized studies, natural experiments, or regression discontinuity studies). Thus, the NRC report of 2012 on deterrence and the death penalty stated that even the very well-done OLS panel data study by Kovandzic et al. (2009) or the Zimring et al. (2010) study comparing the murder rate in Singapore (which ratcheted up its use of the death penalty) with that in Hong Kong (which abolished it at the same time)-both of which found no evidence of deterrence-were "not informative." This may be the purist fallacy of letting the perfect be the enemy of the good: if it were really true that such studies were not informative, one would have to conclude that perhaps 95% of published empirical work in law and economics and virtually every empirical study introduced in litigation should not be undertaken. ...
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I discuss the empirical revolution in law and economics, and use the analysis of the deterrent impact of the death penalty to chart the tremendous advances in estimating causal effects since the mid-1970s. This story highlights how ostensibly sophisticated studies frequently generate incorrect estimates, and how difficult it is to know what studies should be believed—a difficulty open to being exploited by those (the media, think tanks, and others) who seek to promote clearly weak studies for some private agenda. I offer a hierarchy of methodologies to assist in evaluating empirical studies and some suggestions for promoting the search for truth.
... Those criminal justice policies are often based on the concept of deterrence through enhanced enforcement and penalties. As the literature on deterrence indicates, however, homicides are unlikely to be deterred by capital punishment or other sanctions (Tonry 2008;Zimring et al. 2010), and very little is known about the factors that cause homicides to occur with respect to the empirical predictability of homicide outcomes at the individual level. As a result, efforts to reduce homicides are often inefficient and costly. ...
... Ein letzter Fragenkomplex bleibt zu klären; er betont die Bedeutung einer gründlichen Kenntnis der einschlägigen Debatten und der Geschichte des Feldes. Von Thorsten Sellin (1959) bis hin zum Vergleich zwischen Hong Kong und Singapur (Zimring et al. 2010) hat die Entwicklung der Tötungsraten in demographisch ähnlichen Jurisdiktionen mit stark unterschiedlichen Politiken hinsichtlich der Todesstrafe immer den Eindruck erweckt, dass es einen Nulleffekt der Hinrichtungen auf die Tötungsdelikte gebe. Mit anderen Worten: Wenn zwei geographische Zonen Raten von Tötungsdelikten haben, die sich parallel entwickeln, und eine der beiden Zonen ändert ihre Politik hinsichtlich der Todesstrafe drastisch, verhindert dies nicht, dass die Tötungsraten sich weiterhin parallel entwickeln. ...
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Zusammenfassung Die Forschung zur abschreckenden Wirkung der Todesstrafe hat eine in ihrem Umfang beeindruckende Masse an Veröffentlichungen hervorgebracht, deren Aussagen mitunter verwirrend und widersprüchlich sind. Eine Untersuchung der Forschergruppen, die sich mit der Korrelation zwischen Vollstreckungen der Todesstrafe und Tötungsdelikten befassen ergibt, dass es eine „lautstarke Minderheit“ von Untersuchungen gibt, die sich stark für die Todesstrafe aussprechen. Dabei zeigt es sich, dass die Person des Autors eines Aufsatzes zuverlässigere Vorhersagen über die dort zu findenden Korrelationen erlaubt als die verwendeten Daten. Es lässt sich also ein Profil für Autoren erstellen, die häufig zu Ergebnissen kommen, die zugunsten der Todesstrafe sprechen: Es handelt sich um amerikanische Wirtschaftswissenschaftler, die sich selbst nicht als Spezialisten für Verbrechens- und Strafforschung beschreiben und die an einer weniger angesehenen Fakultät als der unterrichten, an der sie promoviert haben. Im Gegensatz dazu kommen Soziologen und Ökonomen an angesehenen Universitäten eher zu dem Ergebnis, dass die Todesstrafe keine Wirkung auf die Mordrate habe.
... A related study, Cochran, Chamlin, and Seth (1994), considers the effect of Oklahoma's first execution in more than twenty years and finds evidence that the execution appears to have increased murder among strangers, an effect they attribute to a "brutalization" hypothesis, though it is attributed with equal ease to statistical noise. A final study worth noting is that of Zimring, Fagan, and Johnson (2010), who compare homicide rates between Singapore, which uses the death penalty with variable intensity, and Hong Kong, which does not use the death penalty. The paper finds no evidence in favor of deterrence, as both countries experience similar homicide trends over the thirty-five-year time period studied. ...
Article
We review economics research regarding the effect of police, punishments, and work on crime, with a particular focus on papers from the last twenty years. Evidence in favor of deterrence effects is mixed. While there is considerable evidence that crime is responsive to police and to the existence of attractive legitimate labor-market opportunities, there is far less evidence that crime responds to the severity of criminal sanctions. We discuss fruitful directions for future work and implications for public policy. ( JEL J64, K42).
... Others find no impact of punishment on crime deterrence (e.g. Zimring, Fagan, & Johnson, 2010;Hjalmarsson, 2009). Evidence on the effectiveness of apprehension is similarly inconclusive (DeAngelo & Hansen, 2014;e.g. ...
Article
For many types of wrongdoings, a deterrent may be a more desirable goal than punishment due to the damage these wrongdoings have already caused and the strain on the resources of enforcement authorities. This paper uses economic experiments to offer insights into the relative effectiveness of monitoring (increasing the risk of apprehension) and punishment severity in deterring dishonest behavior. Experimental results show that varying the degree of punishment severity does not alter self-reported scores on a 5-minute quiz, an indicator of dishonest behavior, given a low risk of apprehension. On the other hand, at a seemingly light punishment level (no gain received), higher risks of apprehension are associated with lower levels of dishonest behavior as seen from lower self-reported quiz scores. These results suggest that the current approach to deterring wrongdoings that usually involve threats of more severe punishment may not be achieving the desired outcome.
... If death penalty is abolished, they will be a menace to the society. (I -/-) Empirical evidence from the USA, Singapore, and Hong Kong suggesting that the death penalty does not produce a greater deterrent effect than can be achieved by a sentence of life imprisonment was thought to be unpersuasive (Cohen-Cole et al. 2009;Zimring et al. 2010). Many espoused intuitive 'beliefs' in deterrence, dismissing the need for statistics to prove a deterrent effect by stating that it was not 'a game of numbers' and that statistics from other countries could not be applied in their country: ...
Article
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India and Bangladesh share a common history, and each has developed somewhat similarly since partition. However, while both countries now have relatively low murder rates, India has seen a decline in the rate of executions, while Bangladesh continues to impose death sentences and carry out executions at a higher rate. There have been challenges to the death penalty in India, restricting its use to exceptional cases. The same has not occurred in Bangladesh. Yet in both countries, systemic flaws in the criminal process are evident. This article draws on two original empirical research projects that explored judges’ opinions on the retention and administration of capital punishment in India and Bangladesh. The data expose justice systems marred by corruption, incompetence, abuses of due process, and arbitrary and inconsistent treatment of defendants from arrest through to conviction and sentencing. It shows that those with the power to sentence to death have little faith in the integrity of the criminal process. Yet, a startling paradox emerges from these studies; despite personal knowledge of its flaws, judges have trust in the death penalty to deter crime and to realise other sentencing aims and feel retention benefits society. This is explained by reference to utilitarian values. Not only did our judges express strongly utilitarian justifications for sentencing people to death, in terms of their erroneous belief in its deterrent effect, but some also articulated utilitarian justifications for misconduct in pre-trial processes, suggesting that it was necessary to break the rules to secure convictions when the system was dysfunctional and ineffective.
... These speculations, especially regarding capital punishment, seem to be borne out in recent empirical research. Zimring et al. (2010) compared murder rates between Singapore and Hong Kong in the last decades, finding that these follow similar patterns in the context of radically divergent capital punishment policies. In this particular case, even Bandura's hypothesis would have to be rejected, since Singapore should have witnessed an increase in the homicide rate, simply in virtue of a much more frequent recourse to capital punishment. ...
Chapter
Law and psychology are disciplines that live in separate wings of the same palace. Both share the goal of predicting and controlling human behavior. However, the law relies necessarily, though often unknowingly or naively, on psychological theories and paradigms it cannot do without. With regard to psychological paradigms, sociological creationism has implicitly expressed the same indifference to which interactionism and other microsociological theories had been condemned, thus repeating the old mistake of placing psychology and sociology on two separate levels that do not communicate. The gist of this critique sounds more or less like this: psychology studies behavioral processes that are inevitably individual and is thus too “contaminated” by the biological factor to offer a satisfactory narrative of social processes.
... Moreover, the deterrence effect of death penalty on crimes has been widely debated in criminological literature (Cloninger and Marchesini 2001;Ehrlich and Liu 1999;Mocan and Gittings 2003;Zimmerman 2004), with empirical studies concluding that this punishment has negligible effects on homicide rates (Zimring, Fagan and Johnson 2010), 10 and drug use (Degenhardt et al. 2008). Critics have also asserted that despite Singapore's claims of effective deterrence and control, the government has rarely published reliable data on rates of drug use or drug-related crimes to allow any independent verification of those claims (HRI 2016; Lines 2018). ...
Article
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This article examines state justifications for capital punishment in Singapore. Singapore is a unique case study because capital punishment has largely been legitimised and justified by state officials. It illustrates how Singapore justifies capital punishment by analysing official discourse. Discussion will focus on the government’s narrative on capital punishment, which has been primarily directed against drug trafficking. Discussion will focus on Singapore’s death penalty regime and associated official discourse that seeks to justify state power to exercise such penalties, rather than the ethics and proportionality of capital punishment towards drug-related crimes. Critical analysis from a criminological perspective adds to the growing body of literature that seeks to conceptualise social and political phenomena in South-East Asia.
... It is quite fair to say that capital punishment as a deterrent remains more an article of faith than a reflection of fact. Even in an Asian setting, a comparison of homicide curves for a 40-year period between Singapore with capital punishment and Hong Kong without it indicates convincingly that the homicide curves have traveled remarkably similar trajectories for the entire four decades [45]. Simply stated, there are no strong empirical grounds for the supposed deterrent effect of capital punishment. ...
Article
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Capital punishment policy deserves a more prominent place in the analysis of the politics of Taiwan. While Taiwan’s political culture is on a par with the mainstream of the world’s democratic politics, its public opinion on capital crime policy is under-researched. This study begins with an historical review of capital punishment in Taiwan. After that, we turn to an in-depth analysis of data from a random survey in Taipei and New Taipei, focusing on the government’s retentionist policy rather than an exploration of general attitudes toward the death penalty. Results indicate that support for death penalty policy and for the Ministry of Justice’s execution policy stems mainly from instrumental sources: Belief in the deterrent effect of capital sentences and faith in a “tough on crime” approach as a generic cure for crime. In contrast, those who believe in the efficacy of rehabilitation tend to oppose capital punishment policy. Unexpectedly, experience with crime victimization and perception of high crime levels in one’s residential neighborhood reduce support for capital punishment policy. We end our analysis with a call to political leaders to exercise enlightened leadership on the death sentence policy.
... These speculations, especially regarding capital punishment, seem to be borne out in recent empirical research. Zimring et al. (2010) compared murder rates between Singapore and Hong Kong in the last decades, finding that these follow similar patterns in the context of radically divergent capital punishment policies. In this particular case, even Bandura's hypothesis would have to be rejected, since Singapore should have witnessed an increase in the homicide rate, simply in virtue of a much more frequent recourse to capital punishment. ...
Chapter
If we can draw a preliminary conclusion from the previous chapters, it is that sociological theory and the social sciences in general have not yet articulated or proposed in a convincing and organic way a theory of the motives of human behavior that can adequately explain the legal phenomenon. In part, this is because, as Gallino (1982, p. 99) has argued, the social sciences have until recently been deprived of a theory of social behavior, stuck as they were in the dogma of social individuality conceived as a blank slate, and in the extremist positions of culturalism.
... It is quite fair to say that capital punishment as a deterrent remains more an article of faith than a reflection of fact. Even in an Asian setting, a comparison of homicide curves for a 40-year period between Singapore with capital punishment and Hong Kong without it indicates convincingly that the homicide curves have traveled remarkably similar trajectories for the entire four decades [45]. Simply stated, there are no strong empirical grounds for the supposed deterrent effect of capital punishment. ...
Article
Capital punishment policy deserves a more prominent place in the analysis of the politics of Taiwan. While Taiwan’s political culture is on a par with the mainstream of the world’s democratic politics, its public opinion on capital crime policy is underresearched. This study begins with an historical review of capital punishment in Taiwan. After that, we turn to an in-depth analysis of data from a random survey in Taipei and New Taipei, focusing on the government’s retentionist policy rather than an exploration of general attitudes toward the death penalty. Results indicate that support for death penalty policy and for the Ministry of Justice’s execution policy stems mainly from instrumental sources: Belief in the deterrent effect of capital sentences and faith in a “tough on crime” approach as a generic cure for crime. In contrast, those who believe in the efficacy of rehabilitation tend to oppose capital punishment policy. Unexpectedly, experience with crime victimization and perception of high crime levels in one’s residential neighborhood reduce support for capital punishment policy. We end our analysis with a call to political leaders to exercise enlightened leadership on the death sentence policy.
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This article will present a series of works in which preventive detention is studied, and group them into three different perspectives: legal doctrine, non-governmental organizations and the social sciences. Finally, we will indicate our position on the matter and it is the one to define the PP in the first place by what it produces, that is to say, by what it is able to articulate. And to develop our position we will identify the different links that originate between the same judicial actors, and between those judicial actors and certain external actors to the criminal justice.
Article
British journalist Alan Shadrake was convicted of contempt of court in 2010 for writing a book about capital punishment in Singapore. This article uses that book and other sources to analyze four aspects of Singapore’s death penalty. It begins with a profile of Darshan Singh, the hangman who executed 1,000 persons over the past half-century. The article then shows that Singapore’s system of mandatory capital punishment does not produce consistency in death penalty decision-making. Next the article argues that the prosecution of Shadrake increased criticism of capital punishment in Singapore by propelling his book to bestseller status. This is followed by an explanation of why the number of persons executed in Singapore has declined in recent years, from an average of 66 per year in the mid-1990s to an average of 5 per year since 2004. The key proximate cause of this decline appears to be prosecutors, who can use their discretion to charge defendants for possessing amounts of heroin, cannabis, cocaine, and methamphetamine that are just under the thresholds for a mandatory death sentence. Capital punishment in Singapore is not really mandatory, and it cannot escape the problems of bias and arbitrariness that have long plagued discretionary death penalty systems in the United States, Japan, and other nations.
Article
Objectives Evaluate the use of various time series methods to measure the deterrence effect of capital punishment. Methods The analysis of the time series approach to deterrence is conducted at two levels. First, the mathematical foundations of time series methods are described and the link between the time series properties of aggregate homicide and execution series and individual decision making is developed. Second, individual studies are examined for logical consistency. Results The analysis concludes that time series methods used to study the deterrence effects of capital punishment suffer from fundamental limitations and fail to provide credible evidence. The common limitation of these studies is their lack of attention to identification problems. Suggestions are made as to directions for future work that may be able to mitigate the weaknesses of the current literature. Conclusions Time series studies of capital punishment suffer from sufficiently serious identification problems that existing empirical findings are compatible with either the presence or the absence of a deterrent effect.
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The present study examines deaths and diseases associated with pollution from coal fired power plants (CFPPs) and compares the volume of those deaths and diseases to deaths and injuries associated with street crimes. This comparison illustrates that the single form of pollution studied here—CFPP small particle pollution—causes more deaths in the US than homicides and deserves additional criminological attention. We frame our examination of CFPP deaths and injuries in the corporate crime and green criminological literatures, and explore CFPP pollution as an example of corporate environmental violence. The widespread nature of CFPP violence justifies focusing greater criminological attention on this issue, including the development of policies for remedying pollution, which is now a ubiquitous problem with severe health consequences.
Article
Social scientists have debated about whether the death penalty and/or executions deter homicides and thus save lives for at least half a century. Recent empirical analyses by Kovandzic, Vieraitis, and Boots (2009) and Land, Teske, and Zheng (2009) implied that if a deterrent effect of executions exists, it is small in magnitude and relatively short term. Discussions of Kovandzic et al. (2009) by Donahue (2009) and Rubin (2009) led to the question studied in this article: Do executions impact felony and non-felony homicides similarly? To address this question and build on recent studies, monthly time-series data on counts of executions and felony-type and non-felony-type homicides in Texas for the years 1994-2007 are analyzed. The results indicate a modest reduction, a deterrence effect, of approximately 1.96 non-felony-type homicides in the month after an execution followed by a rebound in the following second month with a net effect of 1.4 during a 12-month period. By comparison, the corresponding analyses of the felony-type homicide events series produce an estimated increase, a brutalization effect, in the month after an execution of approximately 0.5 homicide events. Combining these two counterbalancing effects produces a slight short-lived deterrent effect of an execution on all homicides taken together. This finding is consistent with the previous findings of Land et al.'s (2009) analyses of all homicides grouped together and with findings from prior studies of felony-and non-felony-type homicides. Policy Implications These findings provide additional evidence that the deterrent effects of executions are modest and short term. In addition, they imply that there would be little, if any, deterrence of homicides in Texas if executions were not used frequently. Recently however, Texas has been a state with (a) a large population, (b) a large number of capital murders and convictions, (c) a continuing stream of convicted murderers sentenced to death, and (d) a willingness to use executions extensively. Whether the modest, short-term deterrent effects of executions found in Texas occur in other states is an open question. But it is evident that few other U.S. states have these four characteristics. At the same time, the downside of the use of executions extensively in Texas is a partially counterbalancing brutalization effect-a slight, short-term increase in the frequency with which perpetrators of felony crimes such as robbery kill in the process of committing the crime. And none of this speaks to ethical or cost-benefit issues in the use of capital punishment as a public policy.
Article
Of methods and men: the social production of knowledge on the effectiveness of the death penalty Rational choice theory has given birth to a massive amount of quantitative empirical knowledge on the deterrent effect of punishment, a field in which results are often confusing and discordant. This paper explores the research communities working on the correlation between executions and homicides, and identifies a « vocal minority » of academics who are very favorable to the death penalty. Knowing the name of the author of an article is a better predictor of the correlations found by the article that the type of data used. This study also shows the typical profile of an author who has a large amount of pro-death penalty results: an American economist, who does not present himself as a specialist in crime and punishment, and who teaches in a faculty ranked lower than the one where he obtained his PhD. On the other hand, sociologists and economists of high-ranking universities tend to find results closer to a « zero » effect of the death penalty on homicide.
Thesis
This thesis consists of three papers in the broad field of Applied Economics. I focus on three “soft factors”, namely, face-to-face communication, brief social interactions and information updates. I study on how they affect individual and organisational outcomes using different natural experiments. The first chapter provides causal evidence on how the ability to communicate face-to-face (in addition to electronic communication) can increase organisational performance. The study exploits a natural experiment within a large organisation where workers must communicate electronically with their teammates. A computerized system allocates the tasks to workers creating exogenous variation in the co-location of teammates. Workers who share the same room, can also communicate in person. The main findings are that face-to-face communication increases productivity and that this effect significantly varies across tasks, team characteristics and working environments. In the second chapter I construct a novel dataset of immigrants and ships arrived to the US in the early 20th century to study the effects of brief social interactions and their persistence over time. The chapter shows that individuals travelling (during few days) with shipmates that have better connections in the US, have higher quality jobs. Several findings are consistent with the mechanism whereby individuals get information or access to job opportunities from their shipmates. The study highlights the importance of social interactions with unknown individuals during critical life junctures. It also suggests that they are more relevant for individuals with poor access to information or weak social networks. The third chapter shows that executions cause a local and temporary reduction in serious violent crime. The interpretation of this result follows from a theoretical framework connecting information updates with the increasing ’awareness’ of individuals about the consequences of crime. Consistently with the predictions of the model, the study finds that effects are stronger when media attention is high and lower in places with high propensity to apply the death penalty.
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In 2014, newly-elected President Joko Widodo announced that Indonesia was facing a national 'emergency' due to high levels of drug use that necessitated harsh criminal justice responses, including the ultimate punishment of death. On April 29, 2015 Indonesia executed eight prisoners condemned to death for drug-related offences, including seven foreigners, eliciting widespread international criticism. This commentary explores the strategies employed and obstacles faced by national anti-death penalty advocates that opposed the 2015 executions, primarily focusing on their efforts between 2015 and 2017. We begin by highlighting existing political narratives that make the death penalty an attractive option for the Indonesian government, before discussing key approaches employed as part of anti-death penalty efforts. It is hoped that a better understanding of existing efforts to promote abolition and the challenges associated with these approaches will help inform a more systematic and evidence-based approach to policy, practice, and discourse on the death penalty for drug-related offences in Indonesia.
Chapter
Homicide is commonly considered as the most serious form of violent crime. This chapter describes the problem of homicide in Asia and reviews empirical research on related issues. It first discusses various international homicide data sources and uses available data to describe the recent homicide trends from 2003 to 2008 in most of the Asian countries and regions. This chapter also reviews the empirical research on the factors that may help explain the homicide trends in Asia. These factors include firearms, capital punishment, population characteristics (such as youth population and population diversity), and social characteristics (such as democracy, modernization, and social stress). This chapter also discusses homicide clearance. The empirical studies reviewed in this chapter either examined specific countries in Asia or included some Asian countries and regions in the comparative analyses.
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Sociological methods have consistently succeeded while econometric methods have failed in research on capital punishment and homicide. But econometricians aggressively promote their findings in public policy venues, while sociologists are less assertive. This is due to cultural differences between the disciplines, and to a philosophy of science that values falsification of hypotheses over progress in answering research questions. This problem has occurred and is likely to reoccur in other policy areas where sociologists are insufficiently assertive in defending their accomplishments.
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Research on the deterrent effects of punishment falls into two categories: macro-level studies of the impact of aggregate punishment levels on crime rates, and individual-level studies of the impact of perceived punishment levels on self-reported criminal behavior. For policy purposes, however, the missing link—ignored in previous research—is that between aggregate punishment levels and individual perceptions of punishment. This paper addresses whether higher actual punishment levels increase the perceived certainty, severity, or swiftness of punishment.Telephone interviews with 1,500 residents of fifty-four large urban counties were used to measure perceptions of punishment levels, which were then linked to actual punishment levels as measured in official statistics. Hierarchical linear model estimates of multivariate models generally found no detectable impact of actual punishment levels on perceptions of punishment. The findings raise serious questions about deterrence-based rationales for more punitive crime control policies.
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Asia is the next frontier in the campaign to end state execution because more than 95 percent of the executions in the world take place there. This book combines detailed case studies of the death penalty in major Asian nations with cross-national comparisons. It demonstrates decline in the number of Asian countries using execution as a criminal sanction and a decline in the rate of executions in most nations that retain the death penalty. Few Asian nations conduct executions with any regularity, and even major nations with death penalties in their criminal codes use the sanction rarely. What separates the low-execution nations from the very few states with high execution rates is, more than anything, politics. All of Asia's high execution states are hard-line authoritarian regimes of the left or right. When former right-wing authoritarian states experience democratic reforms, the rate of executions drops sharply and the only noncommunist government that maintains high executions is Singapore. The key question is not whether Asia will end state executions, but when it can be expected to do so. If the end of executions depends on the democratization of relatively stable hard-line communist regimes, many decades may be required, but if the stigma of state executions continues to increase, the end of capital punishment in Asia could happen before more comprehensive political change occurs.
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Its a book! sorry...frank Zimring
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This paper is the first study to establish that capital punishment's impact is different among U.S. states, deterring murders in some states, but actually increasing murders in many others. Studies by economists, including myself, have typically used large data sets of all 50 states or all U.S. counties to show that executions, on average, deter murders. In contrast, studies by sociologists, criminologists, and law professors often examine only one or a few jurisdictions and usually find no evidence of deterrence. Using a well-known data set and well-tested empirical methods, I find that the impact of executions differs substantially among the states. Executions deter murders in six states and have no effect on murders in eight states. In thirteen states, executions increase murders - what I call the "brutalization effect." In general, the states that have executed more than nine people in the last twenty years experience deterrence. In states that have not reached this threshold, executions generally increase murders or have no significant impact. On average across the U.S., executions deter crime because the states with deterrence execute many more people than do the states without it. The results of this paper help to explain the contrasting conclusions of earlier papers: whether deterrence exists depends on which states are examined. My results have three important policy implications. First, if deterrence is the objective, then capital punishment generally succeeds in the few states with many executions. Second, the many states with numbers of executions below the threshold may be executing people needlessly. Indeed, instead of deterring crime, the executions may be inducing additional murders: a rough total estimate is that, in the many states where executions induce murders rather than deter them, executions cause an additional 250 murders per year. Third, to achieve deterrence, states must generally execute many people. If a state is unwilling to establish such a large execution program, it should consider abandoning capital punishment.
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Cass Sunstein and Adrian Vermeule have argued that, if recent empirical studies claiming to find a substantial deterrent effect from capital punishment are valid, consequentialists and deontologists alike should conclude that capital punishment is not merely morally permissible, but actually morally required. While there is ample reason to reject this argument on the ground that the empirical studies are deeply flawed (as economists John Donohue and Justin Wolfers elaborate in a separate essay), this response directly addresses Sunstein and Vermeule's moral argument. Sunstein and Vermeule contend that recognition of the distinctive moral agency of the government and acceptance of "threshold" deontology (by which categorical prohibitions may be overridden to avoid catastrophic harm) should lead both consequentialists and deontologists to accept the necessity of capital punishment. This response demonstrates that neither premise leads to the proposed conclusion. Acknowledging that the government has special moral duties does not render inadequately deterred private murders the moral equivalent of government executions. Rather, executions constitute a distinctive moral wrong (purposeful as opposed to non-purposeful killing), and a distinctive kind of injustice (unjustified punishment). Moreover, acceptance of "threshold" deontology in no way requires a commitment to capital punishment even if substantial deterrence is proven; rather, arguments about catastrophic "thresholds" face special challenges in the context of criminal punishment. This response also explains how Sunstein and Vermeule's argument necessarily commits us to accepting other brutal or disproportionate punishments, and concludes by suggesting that even consequentialists should not be convinced by the argument.
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A recent cohort of studies report deterrent effects of capital punishment that substantially exceed almost all previous estimates of lives saved by execution. Some of the new studies go further to claim that pardons, commutations, and exonerations cause murders to increase, as does trial delay. This putative life-life tradeoff is the basis for claims by legal academics and advocates of a moral imperative to aggressively prosecute capital crimes, brushing off evidentiary doubts as unreasonable cautions that place potential beneficiaries at risk of severe harm. Challenges to this "new deterrence" literature find that the evidence is too unstable and unreliable to support policy choices on capital punishment. This article identifies numerous technical and conceptual errors in the "new deterrence" studies that further erode their reliability: inappropriate methods of statistical analysis, failures to consider several factors such as drug epidemics that drive murder rates, missing data on key variables in key states, the tyranny of a few outlier states and years, weak to non-existent tests of concurrent effects of incarceration, inadequate instruments to disentangle statistical confounding of murder rates with death sentences and other punishments, failure to consider the general performance of the criminal justice system as a competing deterrent, artifactual results from truncated time frames, and the absence of any direct test of the components of contemporary theoretical constructions of deterrence. Re-analysis of one of the data sets shows that even simple adjustments to the data produce contradictory results, while alternate statistical methods produce contrary estimates. But the central mistake in this enterprise is one of causal reasoning: the attempt to draw causal inferences from a flawed and limited set of observational data, the absence of direct tests of the moving parts of the deterrence story, and the failure to address important competing influences on murder. There is no reliable, scientifically sound evidence that pits execution against a robust set of competing explanations to identify whether it exerts a deterrent effect that is uniquely and sufficiently powerful to overwhelm the recurring epidemic cycles of murder. This and other rebukes remind us to invoke tough, neutral social science standards and commonsense causal reasoning before expanding the use of execution with its attendant risks and costs.
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There is a growing bipartisan consensus that flaws in America's death-penalty system have reached crisis proportions. Many fear that capital trials put people on death row who don't belong there. Others say capital appeals take too long. This report?the first statistical study ever undertaken of modern American capital appeals (4,578 of them in state capital cases between 1973 and 1995)?suggests that both claims are correct. Capital sentences do spend a long time under judicial review. As this study documents, however, judicial review takes so long precisely because American capital sentences are so persistently and systematically fraught with error that seriously undermines their reliability. Our 23 years worth of results reveal a death penalty system collapsing under the weight of its own mistakes. They reveal a system in which lives and public order are at stake, yet for decades has made more mistakes than we would tolerate in far less important activities. They reveal a system that is wasteful and broken and needs to be addressed. Our central findings are as follows: Nationally, during the 23-year study period, the overall rate of prejudicial error in the American capital punishment system was 68%. In other words, courts found serious, reversible error in nearly 7 of every 10 of the thousands of capital sentences that were fully reviewed during the period. Capital trials produce so many mistakes that it takes three judicial inspections to catch them ?leaving grave doubt whether we do catch them all. After state courts threw out 47% of death sentences due to serious flaws, a later federal review found "serious error"?error undermining the reliability of the outcome?in 40% of the remaining sentences. Because state courts come first and see all the cases, they do most the work of correcting erroneous death sentences. Of the 2,370 death sentences thrown out due to serious error, 90% were overturned by state judges?many of whom were the very judges who imposed the death sentence in the first place; nearly all of whom were directly beholden to the electorate; and none of whom, consequently, were disposed to overturn death sentences except for very good reason. This does not mean that federal review is unnecessary. Precisely because of the huge amounts of serious capital error that state appellate judges are called upon to catch, it is not surprising that a substantial number of the capital judgments they let through to the federal stage are still seriously flawed. To lead to reversal, error must be serious, indeed. The most common errors?prompting a majority of reversals at the state post-conviction stage?are (1) egregiously incompetent defense lawyers who didn't even look for?and demonstrably missed?important evidence that the defendant was innocent or did not deserve to die; and (2) police or prosecutors who did discover that kind of evidence but suppressed it, again keeping it from the jury. [Hundreds of examples of these and other serious errors are collected in Appendix C and D to this Report.] High error rates put many individuals at risk of wrongful execution: 82% of the people whose capital judgments were overturned by state post-conviction courts due to serious error were found to deserve a sentence less than death when the errors were cured on retrial; 7% were found to be innocent of the capital crime. High error rates persist over time. More than 50% of all cases reviewed were found seriously flawed in 20 of the 23 study years, including 17 of the last 19. In half the years, including the most recent one, the error rate was over 60%. High error rates exist across the country. Over 90% of American death-sentencing states have overall error rates of 52% or higher. 85% have error rates of 60% or higher. Three-fifths have error rates of 70% or higher. Illinois (whose governor recently declared a moratorium on executions after a spate of death-row exonerations) does not produce atypically faulty death sentences. The overall rate of serious error found in Illinois capital sentences (66%) is very close to?and slightly lower than?the national average (68%). Catching so much error takes time?a national average of 9 years from death sentence to the last inspection and execution. By the end of the study period, that average had risen to 10.6 years. In most cases, death row inmates wait for years for the lengthy review procedures needed to uncover all this error. Then, their death sentences are reversed. This much error, and the time needed to cure it, impose terrible costs on taxpayers, victims' families, the judicial system, and the wrongly condemned. And it renders unattainable the finality, retribution and deterrence that are the reasons usually given for having a death penalty. Erroneously trying capital defendants the first time around, operating the multi-tiered inspection process needed to catch the mistakes, warehousing thousands under costly death row conditions in the meantime, and having to try two out of three cases again is irrational. This report describes the extent of the problem. A subsequent report will examine its causes and their implications for resolving the death penalty crisis.
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This paper derives three LM statistics for an error component model with first-order serially correlated errors. The first LM statistic jointly tests for zero first-order serial correlation and random individual effects, the second LM statistic tests for zero first-order serial correlation assuming fixed individual effects, and the third LM statistic tests for zero first-order serial correlation assuming random individual effects. In all three cases, the corresponding LM statistic is the same whether the alternative is AR(1) or MA(1). This paper also derives two extensions of the Burke, Godfrey, and Termayne (1990) test from the time-series to the panel data literature. The first tests the null of AR(1) disturbances against MA(1) disturbances, and the second tests the null of MA(1) disturbances against AR(1) disturbances in an error component model. These tests are computationally simple requiring only OLS or within residuals. The small sample performance of these tests are studied using Monte Carlo experiments.
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This chapter surveys the theory of the public enforcement of law—the use of governmental agents (regulators, inspectors, tax auditors, police, prosecutors) to detect and to sanction violators of legal rules. The theoretical core of the analysis addresses the following basic questions: Should the form of the sanction imposed on a liable party be a fine, an imprisonment term, or a combination of the two? Should the rule of liability be strict or fault-based? If violators are caught only with a probability, how should the level of the sanction be adjusted? How much of society's resources should be devoted to apprehending violators? A variety of extensions of the central theory are then examined, including: activity level; errors; the costs of imposing fines; general enforcement; marginal deterrence; the principal-agent relationship; settlements; self-reporting; repeat offenders; imperfect knowledge about the probability and magnitude of sanctions; corruption; incapacitation; costly observation of wealth; social norms; and the fairness of sanctions.
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Most papers that employ Differences-in-Differences estimation (DD) use many years of data and focus on serially correlated outcomes but ignore that the resulting standard errors are inconsistent. To illustrate the severity of this issue, we randomly generate placebo laws in state-level data on female wages from the Current Population Survey. For each law, we use OLS to compute the DD estimate of its "effect" as well as the standard error of this estimate. These conventional DD standard errors severely understate the standard deviation of the estimators: we find an "effect" significant at the 5 percent level for up to 45 percent of the placebo interventions. We use Monte Carlo simulations to investigate how well existing methods help solve this problem. Econometric corrections that place a specific parametric form on the time-series process do not perform well. Bootstrap (taking into account the autocorrelation of the data) works well when the number of states is large enough. Two corrections based on asymptotic approximation of the variance-covariance matrix work well for moderate numbers of states and one correction that collapses the time series information into a "pre"-and "post"-period and explicitly takes into account the effective sample size works well even for small numbers of states.
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The reintroduction of capital punishment in 1976 that ended the four-year moratorium on executions generated by the Supreme Court in the 1972 decision Furman v. Georgia has permitted researchers to employ state-level heterogeneity in the use of capital punishment to study deterrent effects. However, no scholarly consensus exists as to their magnitude. A key reason that this has occurred is that the use of alternative models across studies produces differing estimates of the deterrent effect. Because differences across models are not well motivated by theory, the deterrence literature is plagued by model uncertainty. We argue that the analysis of deterrent effects should explicitly recognize the presence of model uncertainty in drawing inferences. We describe methods for addressing model uncertainty and apply them to understand the disparate findings between two major studies in the deterrence literature, finding that evidence of deterrent effects appears, while not nonexistent, weak. Copyright 2008, Oxford University Press.
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How can groups elicit and aggregate the information held by their individual members? There are three possibilities. Groups might use the statistical mean of individual judgments; they might encourage deliberation; or they might use information markets. In both private and public institutions, deliberation is the standard way of proceeding; but for two reasons, deliberating groups often fail to make good decisions. First, the statements and acts of some group members convey relevant information, and that information often leads other people not to disclose what they know. Second, social pressures, imposed by some group members, often lead other group members to silence themselves because of fear of disapproval and associated harms. Hence deliberation often produces a series of unfortunate results: the propagation of errors, hidden profiles, cascade effects, and group polarization. A variety of steps should be taken to ensure that deliberating groups obtain the information held by their members. Information markets have substantial advantages over group deliberation; such markets count among the most intriguing institutional innovations of the last quarter-century and should be used far more than they now are. These points bear on discussion of normative issues, in which deliberation might also fail to improve group thinking, and in which identifiable reforms could produce better outcomes. "Increased accuracy is a common justification for using groups, rather than individuals, to make judgments. However, the empirical literature shows that groups excel as judges only under limited conditions. . . . [G]roups performing tasks that involve solutions that are not easily demonstrable tend to perform at the level of their average members" (See Daniel Gigone and Reid Hastie, "Proper Analysis of the Accuracy of Group Judgments", 121 Psych. Bulletin 149, 1997)."The presumption that Iraq had active WMD programs was so strong that formal