Pilot testing a Post RIDE Evaluation of Alcohol Use by Drivers

Author(s): Paul Boase, Doug Beirness

Slidedeck Presentation Only (no paper submitted):

6C - Boase


Background: In Canada, under provincial/territorial legislation a police officer may stop a vehicle to check the driver’s credentials or the safety of the vehicle. Under criminal statute, the officer must form a suspicion that the driver has alcohol in the body before making a demand for a breath sample using an approved screening device.

The purpose of police alcohol checkpoints is twofold. First, alcohol checkpoints provide a high-profile police enforcement presence in the community increasing the actual and perceived probability of detection, a key element in effective deterrence. Second, by interacting with a large number of drivers, checkpoints provide the police with an opportunity to detect drinking drivers. Research has established a clear and profound impact of checkpoints on alcohol-related crashes.

At police alcohol checkpoints, many drivers, especially experienced drinkers, may not display immediately obvious signs of alcohol use and/or impairment despite a high BAC. During the limited interaction with each driver, police officers are challenged to identify those who may be over the administrative or legal threshold. This is required to establish a reasonable suspicion of driver alcohol use to support a further investigation. Under these difficult circumstances, it is likely that some impaired drivers successfully pass through the checkpoints without the officer being able to form a suspicion to further the investigation.

Aims: The goal of this survey was to set up a secondary alcohol testing location down range from a standard police sobriety checkstop or RIDE in order to assess the effectiveness of police in identifying drivers who had been driving in the limited time and circumstances of a RIDE stop.

Methods: Officers in a mid-sized city setup a standard RIDE operation. The officers performed their regular duties and took the appropriate action the situation allowed. After completing the official police stop, drivers released by the police were then asked to provide a breath sample and answer a few questions. No personal data was requested.

Results: A number of drivers were assessed at the site and a few were detained for further action by the police. In addition, the breath samples indicated that a few drivers who had been drinking were release without further action by the police

Discussion and conclusions: The data do suggest that actual levels of impaired driving have decreased but that some drivers are still using alcohol and driving. Police are can and do detect alcohol in drivers and take action, but in a number of cases, the drivers proceed through the checkstop without further investigation. More checkstops should be evaluated in order to better estimate the size of the problem.