Many people believe that the credibility of the mass media is shrinking. In July 1985, 55 percent of the American people believed that journalists “usually get the facts straight,” according to a study by the Pew Research Center for the People and the Press. By 2001, according to the organization, that number had dropped to 35 percent. A contributing factor to this decline is the belief held by many Americans that the media have let ideological and political biases distort their presentation of the news. A 1998 Gallup poll revealed that 46 percent of Americans believed the news media—especially network television—have a political bias. (The poll revealed a split in what kind of bias, with 27 percent of those polled saying the media had a liberal bias and 19 percent charging that the media had a conservative bias.)

Conservative media critics...