I just came across this glossary on Twitter: Glossary of legal (and related) terms and courthouse signs English/Spanish
I have no idea of how useful it may be, but I like the disclaimer in the introduction:
The Glossary is NOT intended to be an authoritative reference document that
determines once and for all the only correct way to translate an English word or
phrase. While there are certainly many wrong and unacceptable ways to
translate a word or phrase, it is equally true that there is rarely only one correct
way to translate a word or phrase.