Can a prosecutor convict a person of statutory rape with little to no evidence?

Question Details:

I live in MI and the legal age of consent is 16. My friend is 19 and when he was17 and a senior in high school he had sex with a girl that he thought was a junior and also 17. She got mad at him because he basically "hit it and quit it". Since she was actually 15 at the time she knew that statutory rape would be a good way to get him back. She told her parents and they went to the police. My friend got arrested and charged with statutory rape. He has gathered up about at least 12 potential witnesses to prove the lie. There is no DNA evidence and he didn't talk to the police. I want to know what defense would be best? Important Notice