Research demonstrates that police reduce crime. The implication of this research for investment in a particular form of extra police services, those provided by private institutions, has not been rigorously examined. We capitalize on the discontinuity in police force size at the geographic...

We argue that changes in the terror alert level set by the Department of Homeland Security provide a shock to police presence in the Mall area of Washington, D.C. Using daily crime data during the period the terror alert system has been in place, we show that crime drops significantly, both...

We argue that changes in the terror alert level set by the Department of Homeland Security provide a shock to police presence in the Mall area of Washington, D.C. Using daily crime data during the period the terror alert system has been in place, we show that crime drops significantly, both...