Interestingly they do have their own lawyers. The Borg has been for years sending "suitable" Bethelites to Law school (paying for all the expenses) to have their "own" breed of defendants. They only use them in certain kind of cases. If the dirt really hits the fan, they prefer to use "worldly" lawyers, as they can do things that they wouldn't allow their own to do (worldly people are OK, as long as they do the shit work for them!)
Aaaah, I forgot. "Suitable" as in: totally fanatical-brainwashed Gestapo-like guys that will NEVER EVER speak, talk or leave Bet-HELL.
At least every single one that I've meet during my Bet-HELL times was like that.
Now excuse me, bringing those memories up my poor brain, I have to go and or have a few (aaah, who am I kidding, there is not enough booze to make me forget)