seminal study within the congruence tradition was that of Page and Shapiro (1983), who tracked
policy preferences on 231 separate issues between 1935 and 1979 and compared them to trends in
policy decisions over the same period, and concluded that there was congruence 66 per cent of
the time, with opinion usually leading policy decisions. Studies of congruence need not look at
questions on an issue by issue basis. For example, Stimson, McKuen, and Erickson (1995)
constructed highly aggregated liberal-conservative trends in the public mood and law making by
Congress and the Presidency since the 1950s, and found that as the public mood shifts to a more
liberal position, more liberal legislation is passed into law.
A second group of studies look for consistency rather than congruence. These studies do
not track opinion over time but instead examine issues at a single point in time, dichotomizing
public preferences as supporting either the status quo or change, and examining subsequent
policy outputs to see if government decisions are consistent with mass opinion. Evidence of
consistency is established when the public supports change and the government follows, or when
the public supports the status quo on a given issue and the government takes no action on that
issue. Monroe (1998) found a consistency rate of 55 per cent in the US in the period 1980-1993, a
drop of 8 points relative to his earlier study over the 1960-1975 period (Monroe, 1979).
Comparable rates have been found in other countries. In a series of comparative studies on the
US, Canada, Great Britain, France, and West Germany, however, Brooks (1987; 1990) finds
consistency rates that are approximately 20 percentage points lower than other authors.4
One alleged advantage the congruence approach has over the consistency approach is that
it can tell us whether shifts in mass opinion occur prior to changes in government policy or not.
Examining the temporal order of change in opinion and government decisions may, therefore,
offer some clue about the direction of causality in the opinion-policy relationship (something the
consistency approach alone cannot do). However, the congruence approach has several