IV. PROGRAM EVALUATION

B. Connecticut Roadside Survey Direct Measures of Driver BACs

Driver BACs were collected at sobriety checkpoints in nine towns before and after the holiday enforcement periods as a direct measure of the effect of enforcement and publicity on drinking and driving.  A geographically diverse set of sites in the State were chosen, focusing on towns with particularly high alcohol-related fatal and injury crash rates.  The towns were East Lyme, East Windsor, Ledyard, Manchester, New London, Norwich, South Windsor, Stonington, Waterford, and Windsor.  For the July 4th holiday enforcement evaluation, drivers’ BACs were collected in East Windsor, East Lyme, New London, Norwich, and South Windsor.  For the evaluation of the winter holiday enforcement period, driver BACs were collected in each town, excluding East Windsor, for a total of 20 sobriety checkpoints (South Windsor had 2 locations for sobriety checkpoints and thus, held 4 sobriety checkpoints).  The sobriety checkpoints for each evaluation period in each town were held before and after the holiday period at the same location on the same road on the same night of the week at the same time of night.

At sobriety checkpoints, the Connecticut research team obtained voluntary, blind, anonymous BACs from randomly selected drivers on handheld breath testing devices.  These devices (Intoxilyzer 400PA) stored, but did not display, the driver’s BAC reading.  The research team collected anonymous BAC information from the random sample of drivers who were passing through the sobriety checkpoint in one direction in cases where traffic flowed in both directions and the sobriety checkpoint was held on both sides of a road.  Researchers collected this data after the drivers had passed through the sobriety checkpoint.  Researchers interviewed between 80 and 200 drivers at each sobriety checkpoint, typically about 20 percent of the traffic passing in one direction at a sobriety checkpoint.  The interviews consisted of a short set of questions about the type of location the driver was coming from and going to, whether the driver had been through a sobriety checkpoint in the past six months, opinions of sobriety checkpoints, and whether the driver had heard any media messages about special efforts to enforce the laws against drinking and driving.  Researchers estimated characteristics such as age group, gender, race, number of passengers, and type of vehicle after completing an interview with a driver.  Generally, about 92 percent or more drivers agreed to the BAC test.   The team collected 1,249 BAC samples from drivers in the course of evaluating the July 4th holiday enforcement period and 2,115 BAC samples from drivers over the course of evaluating the winter holiday enforcement period.