You are allowed to but you have to give a good convincing history (Not necessarily long.)

As for your second question, not at all.

Regarding one's bounty, you guys start as 0. If you want to be assigned one, include the crime or action your character committed. I'll base it from that. 
Also, everyone should know that having a higher bounty would make your journey more difficulty. So if you have one at the start, you'll definitely get more attention from Marines and Bounty Hunter alike. 

If needed, I will send people to jail. You know, to make it more realistic.