Maybe you've heard the story: Worker gets injured on the job. Employer, anticipating hefty workers compensation claims, administers drug test. Wouldn't you know it, injured employee tests positive for marijuana and is denied compensation due to presumed impairment.

Of course, since marijuana remains detectable for weeks after use, it is just wrong to presume that a positive result indicates impairment at the time of the accident. Still, many companies continue to fire injured employees for marijuana, rather than compensating them for on-the-job injuries that had nothing at all to do with their off-the-job marijuana consumption. It is a morally-reprehensible and scientifically-fraudulent practice, but one which serves the financial interests of its practitioners and thus continues.

Finally, for the first time that I know of, this sickening practice has been challenged successfully in court:

The Tennessee Supreme Court has ruled that a worker whose hand was crushed by machinery at his workplace was not to blame for the accident despite his admitted marijuana use off the job.

…

The state law establishing the drug-free workplace program presumes that any injuries to an employee found to have been using drugs or alcohol were caused by the drug use. But the court noted that the law also allows employees to enter evidence to rebut that presumption.
…

The co-worker and the shop foreman both testified that McIntosh didn't appear to be impaired by marijuana use before the accident.

McIntosh, who had worked at Interstate for five years, contended the injury was caused by the actions of an inexperienced employee. [Forbes]

So often in drug policy reform, we must celebrate victories of common sense that could be taken for granted if anti-drug hysteria had not permeated every aspect of our lives. How absurd is it that McIntosh even had to prove his lack of impairment? After all, it is perfectly clear and undeniable that a positive test for marijuana doesn’t prove impairment at all. There was never any evidence of impairment at any point throughout all of this, yet it had to be decided by the state's highest court.

While the Tennessee Supreme Court has certainly made the right decision here, one shudders to think how many marijuana users have been thrown to the dogs under identical circumstances. The premise that marijuana ruins lives – almost universally false though it is – somehow becomes a justification for profiteers seeking to validate the most despicable treatment of people who've used marijuana.

These events serve to remind us that prohibition is more than police, prisons and politics. It an idea – corrupt to its core – which infects everything, entering our schools and workplaces to spread false prejudice and obscure even the most obvious truths.