What are the laws in Sigil?

I am referring to Sigil, the city floating above the spire in the Outlands. I have looked into multiple different sources, but it seems that there is no clear answer. I have been trying to find some sort of list that outlines what the laws are, but sources seem to contradict each other. One one hand, I am finding some information that says the only thing that would get someone in real trouble would be trying to attack the city at large. I’m also finding other information that suggests there are many different laws in the city.

So which is it? And what are the rules, if there are any? I am not really looking for a list of all crimes possible. What I am looking for are laws that are either specific to Sigil, or that are so serious that they would get a character executed or mazed by the Lady of Pain if they were to be committed.

If the answer to this question is too extensive or complicated to explain, is there a sourcebook that is generally taken as the most accurate or most reliable book about this campaign setting where I can find the information?