53 Pa. Stat. § 23432
There shall be a civil service commission in each city of the second class, consisting of three commissioners to be appointed by the mayor. The persons appointed commissioners shall be men in full sympathy with the purposes of this act. Not more than two of the said commissioners at any one time shall be adherents of the same political party. The commissioners in each city shall be appointed as follows: On the first day of July, one thousand nine hundred and seven, the mayor of each city of the second class shall appoint three commissioners, to serve until the expiration of his term of office and until their successors are appointed and qualified. The mayor shall appoint one of the commissioners president of the commission. Whenever any vacancy shall exist in the office of president of the commission, the mayor shall have the right to appoint any member of the commission the president thereof, and the person so appointed shall serve as president until the expiration of his term. At the expiration of the terms of said commissioners the mayor of each city of the second class shall, after his induction into office, appoint commissioners to serve for the full term of the office of said mayor, and thereafter each mayor on his induction, shall appoint three commissioners, under this act, to serve as civil service commissioners for the full term of his office as mayor. The mayor may, at any time, remove a commissioner, for good cause, which shall be stated in writing and made part of the records of the commission, and fill such vacancy, or any other vacancy which may occur in said commission, by appointment of a successor, to serve for the remainder of the unexpired term. No commissioner shall hold any other office under the United States, the commonwealth of Pennsylvania, or any city or county thereof; nor shall any commissioner serve on any political committee, or take any active part in the management of any political campaign. The salaries of the commissioners shall be fixed by the city councils; and the president of the commissioners shall receive a salary of not less than five hundred dollars per year, and each of the other commissioners shall be paid a salary of not less than two hundred and fifty dollars per year. The commissioners shall qualify by filing with the mayor an oath to perform faithfully the duties of their office.
53 P.S. § 23432