First of all ascertain that what case has been filed against you?
Whether any FIR has been registered, if so what are the sections of law under which you have been charged?
Whether the charge sheet has been filed before court after investigation?
Whether the police have made any arrest?
Whether you have strong documentary evidences to prove that you are not present in the spot on the reported day of commission of offence ?
Whether the high court will quash the FIR or charge sheet is to be noted and how far this evidence will support your claim?
You may ascertain all the above and you can think about filing defamation case only after the case has been quashed by the high court.
Even in the case of high court quashing the case, you have a case against the police which filed the state prosecuted case.
They only can be held responsible for filing this case without making proper investigation into the complaint and also failed to understand that the complaint is false or genuine.
Thus, you can initiate any case against the police i.e., for malicious prosecution.
The proposed defamation cae against the defacto complainant may not be maintainable.
Take the advise of a local lawyer before proceeding blindly on this subject.