People seem to think Marijuana isn't a big deal mainly because it is the Woody Allen of drugs. Problem is federal law disagrees with them. Healy knew that it is illegal to do Marijuana but did it anyways. He gets no sympathy from me.
UFC fighters and many other people now (determined State by State) are perfectly within their legal rights to smoke weed. I don't know where Healy is from, but if he is from a State where Weed is now legal (with more and more to follow) he was well within his rights to smoke weed. The problem is, it wasn't out of his system by the time he was tested. And that's the debate. While the commisions don't say you can't smoke weed on your own time, they say you can't be under the influence during a fight. And with Marijuana, it can stay in your systems for weeks and weeks after you have smoked it and after you are under the influence.
So this has nothing to do with Federal Law. Soon, in most States it won't be a crime to possess and smoke weed. But fighters, need to be sure it's out of their system before they are tested. If it is, they are fine. If not, well, until the rule changes, they will get popped.