Background: Motor vehicle crashes (MVCs) remain a leading cause of death for US law enforcement officers. One large agency implemented a crash prevention program with standard operating policy changes, increased training, and a marketing campaign. This was a scientific evaluation of that crash prevention program. Methods: MVC and motor vehicle injury (MVI) data for law enforcement officers were compared using an autoregressive integrated moving average (ARIMA) model. Two law enforcement agencies who had not implemented a crash prevention program were controls. Results: After program implementation, overall, MVC rates significantly decreased 14% from 2.2 MVCs per 100 000 miles driven to 1.9 (P =.008). MVC rates did not decrease in the control agencies. Overall, MVI rates significantly decreased 31% from 3.4 per 100 officers to 2.1 (P =.0002). MVC rates did not decrease in the control agencies. MVC rates for patrol officers significantly decreased 21% from 3.1 per 100 000 miles to 2.4. MVI rates for patrol officers significantly decreased 48% from 3.2 per 100 officers to 1.6 (P <.0001). Conclusions: Crash and injury rates can be reduced after implementation of a crash prevention program and the largest impacts were seen in patrol officers.