Reading this thread in IMHO gets me wondering. An insurance company wouldn’t test for marijuana use unless that information was relevant some how.
Why would it matter to them? Is the marijuana itself likely to cause people to kick the bucket sooner, or is it more of an associated behaviour kind of thing (people who use marijuana are more likely the type of people who will also do x y and z)?
I think probably the latter. Insurance underwriters look at a couple of “hazards” in this area that are related, but distinct: A “moral hazard” is the risk that the insured will pursue a basically “unsavory” lifestyle due to weakness of character; the specific behaviors involved might or might not incur a greater actual risk, but suggest the person might do other things that are risky. For instance, many pot smokers also smoke tobacco, or might be perceived as more likely to take up smoking tobacco.
A “morale hazard” is the notion that if the person is insured, they’ll be less careful not to incur the losses that the insurance is supposed to cover. For instance, if you buy a Personal Articles Floater to insure your furniture, jewelry, and silver, and you then become careless about locking the house when you leave, that’s the morale hazard.
I agree with what Spectre of Pithecanthropus said. Also there is the hazard of smoking. At best a marijuana user will get smoker rates. Regularly buying an illegal product can put one in risky situations other people may not be exposed to. The chance of accidental death would be higher for someone who is intoxicated a lot. That is similar for alchohol abuse.
Perhaps you are at greater risk for diabetes from all the twinkies and Häagen-Dazs.