Alcohol and driving: application of a definition in a way to deter offenders.

Increasing speed and congestion of vehicular traffic have made the effect of alcohol on the drivers of motor vehicles a matter of growing concern. It is not possible, using the definition of drunken driving that is now prevalent in California, to establish a rule, based on a stipulated minimum concentration of blood alcohol, that will serve to indict most of the guilty yet free all the innocent. If, instead of comparing the suspected driver with the hypothetical "ordinarily prudent and cautious person" as is now done in California, we accept the more widely prevalent definition of driving under the influence which defines the offense as any appreciable diminution in skill ascribable to alcohol, then a blood alcohol concentration of 150 mg. per 100 cc. or even 100 mg. per 100 cc., could suffice for conviction. For the rule as to alcohol content of the blood to be an effective deterrent of drunken driving, all drivers-not just those involved in accidents or observed to drive erratically-would have to be subject to testing.