It’s a suspicion stoked by the fact that, across a range of issues, public policy does not reflect the preferences of the majority of Americans. If it did, the country would look radically different: Marijuana would be legal and campaign contributions more tightly regulated; paid parental leave would be the law of the land and public colleges free; the minimum wage would be higher and gun control much stricter; abortions would be more accessible in the early stages of pregnancy and illegal in the third trimester.

The subversion of the people’s preferences in our supposedly democratic system was explored in a 2014 study by the political scientists Martin Gilens of Princeton and Benjamin I. Page of Northwestern. Four broad theories have long sought to answer a fundamental question about our government: Who rules? One theory, the one we teach our children in civics classes, holds that the views of average people are decisive. Another theory suggests that mass-based interest groups such as the AARP have the power. A third theory predicts that business groups such as the Independent Insurance Agents and Brokers of America and the National Beer Wholesalers Association carry the day. A fourth theory holds that policy reflects the views of the economic elite.

Gilens and Page tested those theories by tracking how well the preferences of various groups predicted the way that Congress and the executive branch would act on 1,779 policy issues over a span of two decades. The results were shocking.