Need Legal Help! please dealing with criminal auto case.?

My Friend is being prosecuted because of an accident that he wasn't even involved in. He doesn't have much money, well like none. Where can he get legal help, do you know of any programs he can get into to get help. He works for the city and its another city who is hitting him with a criminal case even though they don't have somebody pressing charges. In simple here's what happen. He was driving, an accident in front of him happen, he wasn't near the car that got hit, so just like everybody else he left. The next day the CA HP came to his house and told him he hit it and they had witnesses and evidence. Well the evidence doesn't match up, the witnesses recanted but the prosecutor is still going on with the case. Every time he goes back they keep adding more and more stuff. He feels their trying to scare him to sign a plea deal but he won't because he didn't do it. His public defender is good for nothing, is their any way he can get help. He doesnt have money, he's only 20.