In the This-Is-Getting-Ridiculous department:

Blood Test for Marijuana Unreliable for DUI Penalty

Lexington, KY.  Jan. 17  - Once again, a bill that seeks to punish prior use of a controlled substance with an automatic DUI conviction is before the Kentucky legislature.

Like its predecessors, Senate Bill5 cleverly attempts to bootstrap an ill-advised rule regarding all drugs onto a rule created for the purpose of measuring alcohol impairment. Under SB5, a driver who tests positive for traces of marijuana can be convicted of "driving under the influence" even if that driver is unimpaired at the time of arrest.

While such laws do little to actually make roadways safer, they do send many innocent people to jail and saddle them with criminal records for the rest of their lives. Current Kentucky DUI law requires prosecutors to prove that a suspect was impaired while driving. SB5 seeks to circumvent current evidentiary standards by removing this requirement. If lawmakers want to clog court dockets, cost taxpayers more money and make it tougher for Kentuckians to find and retain employment, then this is the bill to support…

Moreover, the test referred to in SB5 is not a test for marijuana impairment, but merely a test for marijuana’s presence, which is not what DUI laws are supposed to punish.

The effect and perhaps even the aim of legislation like SB5 is to punish prior drug use — predominantly marijuana use — by convicting drivers of DUI without scientifically reliable evidence that they were operating a vehicle while under the influence of anything.

"Zero-tolerance" laws are more than unjust; they are scientifically unsound, which is exactly why not one single state applies such a rule to alcohol. Furthermore, these laws are even less suited for marijuana, the traces of which are detectable by drug tests long after its intoxicating effects have worn off…

A driver with high levels of THC (the active psychotropic ingredient in marijuana) in the blood may not be impaired in any manner if time has passed since the substance was last used. The inability to accurately measure marijuana impairment is why both the National Highway Traffic Safety Administration and the National Institute on Drug Abuse have stated that marijuana impairment testing via blood sampling is unreliable.

Driving under the influence of any substance is dangerous and should not be tolerated, but sending innocent people to jail for DUI using methods incapable of accurately measuring impairment is not the answer. 
  

(Thanks to Nathan Miller) 

Interesting review concluding that certain common prescription drugs are causing a craving for alcohol and, possibly, alcoholism: 

Alcohol Cravings Induced via Increased Serotonin

There is an alarming connection between alcoholism and the various prescription drugs that increase serotonin. The most popular of those drugs are: PROZAC, ZOLOFT, PAXIL, LUVOX, SERZONE, EFFEXOR, ANAFRANIL, and the new diet pills, FEN-PHEN and REDUX. For seven years numerous reports have been made by reformed alcoholics (some for 15 years and longer) who are being "driven" to alcohol again after being prescribed one of these drugs. And many other patients who had no previous history of alcoholism have continued to report an "overwhelming compulsion" to drink while using these drugs…

For some time we did not have specific medical documentation to help us understand why this was happening. Could it be that Prozac, Zoloft, Paxil, etc., being mood altering substances, were removing the inhibitions that individuals had placed upon themselves to stop their additions? But beyond this mood altering effect of Prozac, etc., there seemed to be a physiological cause for this alcoholic obsession as well. There were reports of people who rarely drank before Prozac, etc., consuming excessive amounts of alcohol after starting usage of these various drugs.

In November of 1994 Yale published a study that gave us one answer to the alcohol cravings associated with these drugs. The study demonstrated that an increase in brain levels of either of two neurotransmitters (brain hormones), serotonin or noradrenalin, produces: #1 a craving for alcohol, #2 anger, #3 anxiety. They found this to be especially true for those who have a history of alcoholism…

The Yale study mentioned is Specificity of Ethanol-like Effects Elicited in Serotonergic and Noradrenergic Mechanisms," ARCHIVES OF GENERAL PSYCHIATRY, Vol. 51, Issue 11, pgs 898-911.

(Thanks to William C. Head.)