Who Watches the Watchmen? Local News and Police Behavior in the United States

Nicola Mastrorocco (Trinity College Dublin)
Arianna Ornaghi (University of Warwick)

Abstract: How do the media influence local institutions? We explore the question by looking at how acquisitions of local TV stations by a large broadcast group affect U.S. municipal police departments. To capture variations in local media, we implement a triple differences-in-differences design which exploits the staggered acquisition of local TV stations by the Sinclair Broadcast Group 2010-2017, together with cross-sectional variation in whether municipalities tend to be covered by local news at baseline. First, using a newly collected dataset of transcripts of 300,000 local newscasts, we document that once acquired by Sinclair, local TV stations decrease local crime news coverage. Second, we find that after Sinclair enters a media market, municipalities that were likely to be in the news at baseline experience 8% lower violent crime clearance rates with respect to municipalities that were very rarely in the news. Our preferred interpretation is that the change in content induces police officers to decrease the effort allocated to cleaning violent crimes. We show that this reduction in police effort is not explained by underlying changes in crime rates but, rather, by a decrease in the importance and salience of crime as a topic in the public opinion.