The last of three Penobscot County Jail guards involved in roughing up an inmate last spring has prevailed in challenging his punishment.

The other two also had fought their disciplinary actions and had succeeded in getting them eliminated or lessened.

The County Commissioners last week erased Corrections Officer Ed Arthurs’ six-week suspension and ordered back pay for him. The decision resulted from a closed-door hearing a week earlier.

After a 3 1/2-month investigation, Sheriff Edward J. Reynolds disciplined the guards after an inmate was manhandled early the morning of March 10, while being booked at the jail.

Cpl. Robert Howell was suspended for 12 weeks and Sgt. Joseph Leen lost his job altogether. Last summer, the commissioners reinstated Leen and gave him back pay, and cut Howell’s suspension in half.

Of the three, Arthurs was the only one who didn’t belong to the union and who, therefore, didn’t have union representation in appealing his punishment. He filed his complaint through an attorney.

The details of the incident became public last summer, when Leen’s grievance hearing took place in open session at Leen’s request.

The inmate, who had been drinking, was characterized during that hearing as the most combative inmate anyone on duty that night had seen at the jail. During the two hours before he was bailed, the inmate’s head was smashed against a table, and he was placed in a choke hold and slapped in the face.

The rough treatment was reported by a Bangor police officer — the son of the jail administrator — who witnessed it while bringing another inmate to the jail.