Drunk driving laws are really addressing the problem indirectly. The whole point is that EtOH affects stuff like reaction time, motor control, situational awareness, and risk assessment. The source doesn&#x27;t matter, if you are not able to meet a minimum ability in those skills, then driving is a going to be dangerous. The source of the problem doesn&#x27;t matter.<p>Instead of the breathalyzer (or other tests for EtOH) we should be testing for ability. I suspect this shouldn&#x27;t be hard or expensive, for example, to make a  portable device that implemented objective tests[1] of ability. Obviously some research would be needed to determine which skills need to be tested and to calibrate the minimum-ability cutoffs.<p>[1] like this reaction time test: <a href="https:&#x2F;&#x2F;faculty.washington.edu&#x2F;chudler&#x2F;java&#x2F;redgreen.html" rel="nofollow">https:&#x2F;&#x2F;faculty.washington.edu&#x2F;chudler&#x2F;java&#x2F;redgreen.html</a>