Accessing information about interest group advertising content

Interest groups scholars often want to track the political involvement of groups through their advertising, but there is no one source that covers the universe of advertising. We report here on three of the most commonly used and comprehensive data sources on group-sponsored advertising in the USA, noting the strengths and weaknesses of each. These data sources are the Federal Communications Commission (FCC) Web site, the Wesleyan Media Project, and the Facebook ad library. We focus on both the completeness of the information provided and the ease of accessing the information. We conclude that the strengths of each database differ. FCC data are good for a comprehensive view of a particular state or media market. WMP data are great for information on television spending and content, while the Facebook library, in spite of bugs, provides the best data on digital ad spending and content.