Whose Opinion Matters?

On Monday, the Senate voted 51-45 (nine votes short of the supermajority needed) to block debate on the Buffett Rule that would have required millionaires to pay an income tax rate of at least 30%. A CNN poll showed that 72% of Americans favored the rule. This is just one of many policies—from ending the war in Afghanistan to providing a public option for health insurance—that were favored by a majority of Americans, but not by corporations or wealthy Americans, that have been defeated. How responsive is our political system to public opinion? And to whose opinions does it respond?

These questions are difficult to answer. Prevailing research can only tell us how well legislation corresponds to public opinion, and whose opinions it matches. In other words, we can look at the correlations between the attitudes of the population—or population subgroups—and political decisions. But if a positive correlation is found, that doesn't necessarily mean that the people are influencing their legislators' votes. The politicians could have persuaded the public to accept their policies. Or both the public and their legislators could be reponding to a variety of third variables, such as their shared background, real world events, or media coverage of political issues. Therefore, instead of talking about the public's “influence” on politicians, I will refer to the “consistency” between their opinions.

Early studies of consistency used the box-score method, comparing the majority preference on a particular issue, as indicated by public opinon polls, to subsequent legislative decisions. Chance alone would ensure that legislators would agree with the majority half the time even if they completely disregarded public opinion. Political scientist Alan Monroe found that in over 500 Congressional decisions between 1980 and 1993, the outcomes corresponded with public opinion 55% of the time. This was better than chance agreement (50%), but not much better. If our legislators follow the wishes of the majority 55% of the time, does this mean that we have a responsive government? Monroe reports that between 1960 and 1979, agreement was 63%, so whatever it means, it's going down.

Larry Bartels studied differences in the consistency of U. S. Senators' votes with the attitudes of their constituents of different social classes. He measured the relationship between participants' self-ratings on a 7-point liberalism-conservatism scale and all the decisions made by their Senators between 1988 and 1992. The respondents were divided into approximately equal thirds by income. (For convenience, I'll call them the “rich,” the “middle class” and the “poor.”) Through a complex (but not controversial) mathematical procedure, Bartels estimated the “weight” that should be given to upper, middle and lower class opinion in order to produce the best match with the Senators' decisions.

The opinions of both the middle class and the rich corresponded with the choices of their Senators, but the weight associated with the opinions of the rich was about 50% greater than the weight of the middle class. The opinions of the poor, however, were given no weight at all. (Their opinions were actually slightly negatively related to their Senators' votes.) These class differences were not as great on social issues, such as abortion, as on economic issues, but in all categories, rich people's views were most consistent with the outcome, and the views of the poor were unrelated to the outcome. Of the specific bills Bartels studied, the greatest inequality occurred on a proposal to increase the minimum wage. Here, neither the wishes of the poor nor the middle class had any weight at all, and the decision corresponded exclusively to the opinions of the rich. (I don't need to tell you what the Senators decided.)

Bartels divided the Senators by party affiliation. He found that the Elephants' votes were about twice as consistent with the views of the rich as the Jackasses' votes. Both parties were equally responsive to middle class opinion and equally unresponsive to the poor.

Martin Gilens compared the results of surveys (conducted between 1981 and 2002) asking people whether they favored 1781 proposed policy changes to subsequent votes on those policies. This allowed him to locate the best-fitting curve relating public opinion to Congressional decisions. He found a strong status quo bias. That is, as the percentage of people favoring a policy change increased, its probability of being enacted also went up, but even when a policy had 90% support, its probability of passing was only 46%.

He then divided the country into ten deciles according to income, and compared the opinions of people who were richer than 90% of Americans to the opinions of eight other groups, all the way down to the 10^th percentile of the income distribution. He found that the votes were consistent with the preferences of all ten economic subgroups, but as wealth increased, the correpondence between their preference and the decision increased. However, this analysis may have overestimated the consistency of the attitudes of the poor with politicians' votes, since in most cases they agreed with the rich. Gilens then did an analysis of the 887 cases in which there was significant diagreement on the policy among people at different income levels. Here are two charts showing these results.

The top chart compares the consistency of legislators' votes with people at the 90^th and 10^th percentiles of the income distribution. The positive slope of the 90^th percentile line indicates that as more rich people favor the policy, its probability of passage goes up. On the other hand, the 10^th percentile line is flat, indicating that the opinions of the poor are unrelated to the outcome. The bottom chart compares the rich with the middle class (the 50^th percentile). Unlike the poor, the middle class appear to have some influence, but of course not as much as the rich.

Why do the views of the rich carry more weight? Maybe they're more likely to vote, more likely to contact their Senators, or more knowledgable about current events. The surveys Bartels used asked participants to state whether they had voted or contacted their Senators. It also included a measure of political knowledge. Since all three of these measures were positively related to income, they were all associated with greater consistency between the respondent's views and those of the Senators. However, statistically controlling for turnout, contact and political knowledge reduced the difference between the apparent influence of the rich and poor by only 24%.

Unfortunately, the survey did not ask participants whether they had made political contributions. Looking at other data on campaign contributions by income level collected at that time, Bartels estimated that if the Senators had based their decision only on contributions, they would have given six times (600%) more weight to the views of the rich than the middle class and almost no weight to the poor. The actual disparity in weight between the rich and the middle class (50%) was not as great as the differences in contributions would have predicted.

I'm bothered by the fact that in these studies the "rich" are defined as either the top third of the income distribution (Bartels) or the 90^th percentile (Gilens). These subgroups include some people who might be considered upper middle class. It would be interesting to know how consistent the opinions of the top 1% are with those of the politicians. Gilens data seem to imply that as wealth increases, agreement also increases. Is there any upper limit to this effect?

Of course, these data are mostly from the 1980s and 1990s.  Over time, both the absolute amounts and percentages of campaign contributions coming from the rich have increased. This is probably especially true since the 2010 Citizens United decision, which allows unlimited contributions by corporations and the rich. But since the decision also allows these contributions to be anonymous, their impact will be difficult to measure.

Those who believe the U. S. political system is a plutocracy rather than a democracy will find these data to be at least consistent with their theories, particularly on economic issues, although the middle class's opinions are given almost as much weight as those of the rich when the issue is of little economic importance. The poor, however, have been effectively disenfranchised when their opinions differ from those of the rich. Given the secrecy with which political decisions are made, it will be difficult to find conclusive proof of quid pro quo corruption.