The Law of Non-Contradiction is manifestly false in the arena of legal reasoning, at least in common-law jurisdictions such as the United States. Given just about any desired conclusion, one can come up with a logically valid legal argument in favor of it.. (I can't speak for how things are done in civil law jurisdictions, such as France.)
I was just wondering. Human minds are messed up in 1001 ways, but are there a few rational principles that most people already have down? Of course, the answers to this question are probably so extremely obvious that I haven't even considered them. But I ask all the same.