As I understand it, murder in space is easy to deal with. You simply call a meeting to decide who the murderer was. After a majority vote, the guilty party is evacuated from the airlock.
In theory yes, but in practice you'll most likely to face the following issue: in space, people often are specialists. So what if the mechanic goes bananas, kills someone and then it turns out he is the only one with some in-depth knowledge of the engines and letting him out may be even more risky than keeping on board.
Nobody said it can't be dealt with at all. Where's the justice in your approach though?
It's a joke about Among Us.
Justice is certainly a sliding scale. The remote, dependent culture of a space station may have to make hard decision. For instance, out the airlock with the plaintiff because they are expendable and the accused is the only one who can maintain the air recyclers. And so on.