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Traffic injury Research Foundation

About Interlocks



The alcohol interlock is a monitoring tool that, when coupled with appropriate reporting and supervision, can be effective in controlling the behaviour of alcohol impaired drivers. Alcohol interlock devices have become increasingly popular as a means to prevent persons convicted of an impaired driving offence from repeating the behaviour. They function as a form of incapacitation and serve as a bridge between licence suspension and full licence reinstatement. Alcohol interlocks allow offenders to operate a vehicle legitimately within the driver licensing system while at the same time provide the public with the assurance that offenders will only be able to drive when their BrAC is below a specified value. An impressive volume of research has concluded that alcohol interlocks reduce recidivism rates among both first time and repeat offenders while the interlock is installed in the car. During the period of interlock installation (i.e., while the device is installed in the vehicle) alcohol interlock users have lower total recidivism compared to non-users. These research results are consistent in the United States and Canada.