Bonnie Jean: I would talk to a Family Lawyer and tell them what you have told us. If you cannot afford a Lawyer, talk to someone at the local women's services center or see if there is anyone doing "pro bono" (free) legal help at your nearest Bar Association. Someone like him should only get supervised visitation, and, if he continues to get into trouble, in my opinion, he should lose his parental rights. I would think, since he has gotten arrested and he raped you, if he/she knew this, that they would not side with your child's father any longer.
Did you file charges at the time of this alleged rape? If not, and you're trying to use this allegation to slander your ex to gain an advantage in court...its not going to work. If you did file charges, why hasn't this come up already in your custody battle.
Basically, you can't go back almost 4 years later and say "I should have custody because he raped me" if you didn't file charges.
In addition, it sounds like you both have issues with the law. I don't see you gaining an advantage there either. Being in jail isn't necessarily a reason to lose custody of the child.
If I were you, my approach would be different. Custody cases are NOT won by slandering the other party in court. They're won by proving why you are the better person to have full custody.
And unless there's something really wrong with this guy...its not in your child's best interest to not have a relationship with her father...so tread lightly.
Courts aren't siding with him or you. They side with the best interest of the child. When you start focusing on that as well...you'll do a lot better in court.
Definitely seek some legal advice but I believe you should reconsider your focus. Think about what's best for your little girl longterm.