What can i do?

I have a friend that is in jail now over a child support case. His wife is saying that he owes over $60,000.00 in back child support they have been legally seperated since 1998 i believe. He can not get a good job worth anything b/c he has a prior minor assault on his record. He does not have a car which makes it even harder for him. They are asking him to pay around $200.00 per week. You would have to have a job make over $15 dollars a hour just to be able to live and support yourself. Is there anything that he can go to court and say or do that would give him some relief in this case. I know that he is in the wrong some what but I believe that he does not owe this amount and he does not have proof of the records of paying b/c they got burnt in a fire. Can he get a public defender and would they even be able to help him with getting this amount reduced or some relief? I don't know if you would even begin to help me with this but any help is good. Thank you so much for your time.