53 Pa. Stat. § 22532
No person shall be employed in this department as a policeman or fireman who is not a citizen of the United States, or who has been convicted of crime, unless pardoned, or who cannot read and write understandingly in the English language, or who shall not have resided within the State at least one year preceding his appointment.
No policeman shall be required to be on duty for more than nine out of any twenty-four consecutive hours, nor for more than forty-four hours in any calendar week, and every policeman shall be allowed to have at least forty-eight consecutive hours off duty in every calendar week, except in emergency cases for the suppression of riots or tumults or the preservation of the public peace in times of riot, conflagration, or public celebrations; and in such cases, council shall provide for the payment of extra compensation or time off at the same rate as paid for regular service. The existing salary or compensation of any Policeman shall not be diminished because of the reduced number of hours of duty prescribed by this amendment.
53 P.S. § 22532