American journalism sounds much more Democratic than Republican

Public trust in American media has plummeted since the 1990s. Most of this decline is among conservatives, spurred by Republican charges of liberal bias from avowedly non-partisan outlets. Such claims are hard to assess fairly: stories viewed by one party as following the facts are often seen by the other as ideological.

Most public estimates of news sources’ partisan leanings rely on subjective ratings. Political scientists seeking an objective approach have used the language in politicians’ speeches to set a baseline and compared stories with that. However, most studies in this...