Z Man goes over a number of possible pro and con consequences of drug legalization here, worth a read. I’d like to hilight the following:

We also have a lot of ways of dealing with drunks. Where the written law ends, the unwritten laws begin. American society has lots of unwritten rules for mitigating the effects of legal alcohol. Those unwritten rules have not yet materialized with regards to legalized weed. Can an employer refuse to hire someone who is a casual user of cannabis? Can we develop a test to know if someone is too impaired to operate a motor vehicle? If marijuana legalization is going to go forward, the culture will change in response.

This touches on a point I’d long made when discussing drugs with people in the services who knew my generally libertarian-ish (more so at the time, but even then never “big ‘L'”) stances, who wondered why I was death on drug use by servicemen and not inclined to legalize any time soon. it boils down to one word: responsibility.

Namely, we can pull a guy aside and draw blood or have him take a breathalyzer test, and get a reasonable indication of how impaired they are, right now, or over the last several hours, if negligence is an issue. A dockworker gets drunk off the yard during his lunch break and screws up operating a crane? We can prove he was drunk.

Not so with most drugs, especially the common ones like Marijuana that we test for, and get indications at best that it’s been used over the last several days or weeks, with no firm indicaiton of whether or not that was recent enough the person tested is still impaired.

The last thing I want is anyone near cranes, other lifting gear, or operating seawater safe, reactor systems, or even everyday vehicles impaired. While the military can still ban their use if legalized on the civilian side, to the best of my knowledge we still can’t test for current state of intoxication other than alcohol, we have no way of busting a guy for DUI, negligence, etc., especially if deaths and property damage are involved.