Does the media matter? A field experiment measuring the effect of newspapers on voting behavior and political opinions

There is substantial evidence that media sources have identifiable political slants, but there has been relatively little study until recently of the effects on political views and behaviors of media bias or access. This paper reports the results of a natural field experiment to measure the effect of exposure to newspapers on political behavior and opinion. The Washington DC area is served by two major newspapers, the Washington Times and the Washington Post. We randomly assigned individuals either to receive a free subscription to the Washington Post, to receive a free subscription to the Washington Times, or to a control group. We then conducted a public opinion survey after the 2005 Virginia gubernatorial election. We find that those assigned to the Post treatment group were eight percentage points more likely to vote for the Democratic candidate for governor than those assigned to the control group. We find similar but weaker evidence of shifts in public opinion on specific issues and attitudes.