The MBTA’s new push to check tickets on commuter rail platforms has yielded its first arrest. Problem is, the passenger had a valid ticket — and a bit of an attitude.

Jim Yarin, a 58-year-old Acton resident and longtime commuter rail passenger, had already paid for an entire month of rides with an October pass. He was detained last week by Transit Police on a North Station platform and charged with trespassing after the ticket checkers said they could not verify that his paper ticket was valid.

Yarin concedes that he could have avoided arrest but says he escalated the situation out of principle.