if the police search your car and find two brand new computers,and assume the computers are stolen,and take you to jail for possession of stolen property.then the d.a. drops the charges.don't the police have to give you back your computers?
No. The D.A. may feel there is insufficient evidence to convict you [not showing you knew the computers were stolen] but that the computers were stolen.
If you want the computers back, you are probably going to have to file a motion in the criminal case. I suggest speaking to an attorney that is familiar with forfeiture and return of property motions in the context of criminal law.