All of the reviews of the scientific evidence on traffic safety measures that do the most amount of good rank lowering the blood alcohol level extremely highly. So sobriety checkpoints, if well publicized, with lots of media attention, do have a significant deterrent impact, but a 0.05 BAC would appear to be the second most effective measure. The most effective measure in driving down impaired driving deaths and injuries is random breath testing. A lower blood alcohol level is number two, from all of the reviews of the literature.
