How safe are trick-or-treaters? An analysis of child sex crime rates on halloween.

States, municipalities, and parole departments have adopted policies banning known sex offenders from Halloween activities, based on the worry that there is unusual risk on these days. The existence of this risk has not been empirically established. National Incident-Base Reporting System crime report data from 1997 through 2005 were used to examine daily population adjusted rates from 67,045 nonfamilial sex crimes against children aged 12 years and less. Halloween rates were compared with expectations based on time, seasonality, and weekday periodicity. Rates did not differ from expectation, no increased rate on or just before Halloween was found, and Halloween incidents did not evidence unusual case characteristics. Findings were invariant across years, both prior to and after these policies became popular. These findings raise questions about the wisdom of diverting law enforcement resources to attend to a problem that does not appear to exist.