Legal Advice (Before leaving a university campus I went around to collect bikes that were left behind)?

Before leaving a university campus I went around to collect bikes that were left behind. The campus had already been cleared out and several things were left behind, (futons, trash, etc). After putting 2 bikes in my car and riding back on 1 was arrested by the police for theft. I did not (cut) any bikes and acted with brevity and honesty when questioned by the police. I was surprised to be arrested as many people I know have collected bikes like this before that were left behind. My guess is to plead to contest in court and hope to have a post trial diversion or charges dropped. Any advice?