Police generally set up sobriety checkpoints in areas where there are a high number of DUI arrests or alcohol-related accidents. Sobriety checkpoints are most commonly found between the hours of 9 p.m. and 2 a.m. on weekends and holidays, and in areas near bars and other drinking establishments, reports DUICheckPoints.net
Sobriety checkpoints may also be located near large events, such as concerts and sports games. Police generally announce when and where they intend to place a sobriety checkpoint, according to Nolo.com. Publicity surrounding police presence at checkpoints is believed to serve as a deterrent to drunk drivers. The Governors Highway Association publishes a list detailing each state's policy on sobriety checkpoints and their frequency of operation.