The foregoing board of joint city and county workhouse directors shall have power to establish rules and regulations under which, and specify the conditions on which, any prisoner may be allowed to go upon parole outside of the buildings and inclosures, but to remain while on parole in the legal custody and under the control of the board and subject at any time to be taken back within the inclosure of said institution; and full power to enforce such rules and regulations and conditions, and to retake and reimprison any convict so upon parole, is hereby conferred upon such board, whose written order, certified by its secretary, shall be a sufficient warrant, for all officers named therein, to authorize such officer to return to actual custody any conditionally released or paroled prisoner; and it is hereby made the duty of all officers to execute such order the same as ordinary criminal process; and the board may employ or authorize any person or persons to see that the conditions of such paroles are not violated, and in case of such violation to return any such prisoner so violating such parole to said workhouse, and the time between the violation of the conditions of such parole or conditional release (by whatever name), as entered by order of the board in the record of its meetings, and the reimprisonment or return of such prisoner shall not be counted as any part or portion of time served under any sentence; and any prisoner at large upon such parole who fails to return to the custody of said workhouse as may be specified as one of the conditions of his parole, or commits a fresh crime and is convicted thereof, shall be, on the order of such board, treated as an escaped prisoner and subject to the penalties concerning escapes from prison.