I'm curious, what if your a legal card holder but you choose not to smoke or consume, wouldnt they have to prove that you're an actual user?
The question is whether or not you are actually USING cannabis, not just whether or not you have a prescription for it.
Card or no card, if you don't use, you can honestly answer "no" and legally purchase a gun. Nobody has to "prove" anything.
If you ARE a user you've got two choices:
a- Dishonestly answer "no" (which is itself a crime), or
b. Answer "yes" then be ineligible to purchase a gun via any dealer. I think also, that if you're EVER flagged on a 4473, you're "permanently" flagged, and you will have trouble buying a gun from that point on, even if you later stop using and can honestly answer "no".
Note that in at least some States, its perfectly legal for adults to purchase guns from each other in face-to-face transactions *without* doing Federal paperwork. This ability has been deliberately mislabeled by gun-haters as the "gun show loophole" even though every law applying to gun sales everywhere else in the State also, obviously, applies at gunshows.
So depending on how the law is worded in your particular state, being an MMJ user may NOT completely bar you from legally buying or possessing guns, so long as you obtained them in face-to-face transactions from non-dealers only. (And note that its against Federal law for anyone to buy a gun from a dealer with the intent to transfer it to someone else who isn't otherwise allowed to have it).
having the card shouldn't justify their rulings. also anabolic steroids are considered a controlled substance under federal law. so if I have a local doctor prescribing me testosterone for a deficiency, then should I also be considered as a illegal guns carrier?
First of all, by definition all prescription drugs are "controlled substances". (IE if they're regulated enough that you need a prescription to get them, they're "controlled"). That's not really what's important here, though. One more time, here is the relevant statement on the 4473 form you have to fill out if you want to purchase a firearm from any Federal Firearms Dealer:
"Are you an unlawful user of, or addicted to, marijuana or any depressant, stimulant, narcotic drug, or any other controlled substance?"
Since testosterone is not a narcotic, stimulant, depressant or addictive, and since you would be using it legally under direction of a physician in this case, you can honestly answer "no" to this question, and therefore not disqualify yourself from legally purchasing a gun.
The same would be true of any non-addictive prescription drug, or even addictive ones, so long as you weren't addicted! But even if you are using legal prescription drugs under the direction of a physician, if they're addictive and you're addicted, then you can't honestly/legally answer "no" to this question.
If you're talking about non medically supervised use of anabolic steroids (ie "juicing") then that's illegal, and if you were "juicing" then without a doctors prescription then you couldn't truthfully answer "no" to this question. On the other hand, if you managed to find some physician crazy enough to write you prescriptions for anabolic steroids, then you wouldn't be using them illegally and could answer "no" legally.
Now, lets say you're a "midnight toker" and you just lie on your 4473 form. What would happen?
In practice, probably nothing. The BATFE doesn't test gun buyers for drugs at the point of purchase, and so far as I know they have no mechanism for doing so. It would be pretty difficult for them to ever find out that you've been smoking, and then to prove that in a court of law, especially since drug-related crime is really outside of their jurisdiction. So while its never a good idea to violate the law, in practice, in this situation so long as you didn't generate a drug-related criminal conviction for yourself, you'd "probably" still get away with it.
