Drug tests show positive even when the person isn’t impaired is the problem. What you do outside of work, on private property, is not any of your employees business.

Not only that, but drug tests show positive even when the person isn’t actively impaired.

Assuming someone has “negative effects” because they use drugs is kinda shitty.

Being that it’s Microsoft, I’m sure they will be.

Washington is an at will state. They can fire you because they don’t like your shirt color. Why they did it is anyone’s guess. Your colleague can request a reason for termination in writing and the company is obligated to provide one.

I have no insight on your second question.

What? How is this question hurting you in any way?

I understand trans rights and inclusivity, which I am making an assumption this is about, but someone asking this question doesn’t have anything to do with that. And if you are actually offended by this, this is why no one takes this shit seriously. I’m not saying you can’t be offended, but this is one of those times where some self awareness needs to come into play, and you need to understand that just because you were offended doesn’t mean someone meant to offend you; or that they need to change something they did. This is a perfectly acceptable question and it will be until we stop having doors in every establishment that say “MEN” or “WOMEN” on the door.