Yes, in Mexico it's a well understood term, I think.
I forgot about that word in the previous post.
- Usted no es abogado; es un leguleyo que sólo quiere dinero. (You're not a lawyer; you're just a shyster hungry for money.)
- El juez tomó una decisión injusta, como un vulgar leguleyo. (The judge made an unjust decision, as a lawyer who doesn't know the law.)
- ¿Crees que me asustas con tus trucos de leguleyo? (Do you think I'm scared by your pettifogger tricks?)