53 Pa. Stat. § 23431
On and after the first day of July, one thousand nine hundred and seven, appointments to, and promotions in, the civil service of the cities of the second class shall be made only according to qualifications and fitness, to be ascertained by examinations, which, so far as practicable, shall be competitive, as hereinafter provided. On and after the said date, no person shall be appointed, transferred, reinstated, or promoted, as an officer, clerk, employé, or laborer, in the civil service under the government of any city of the second class, in any manner or by any means other than those prescribed in the act: Provided, however, That among those persons possessing equal qualifications and eligible for appointment to any office, preference in appointment shall be given to honorably discharged soldiers and sailors who served in the Army or Navy of the United States during the War of the Rebellion, or to honorably discharged soldiers, sailors, and marines, who served in the armed forces of the United States or its Allies during its war against the Imperial German Government: Provided further, however, That if the preference hereby provided for be for any reason invalid, all the other provisions of this act shall remain in force with like effect as if said preference had not been contained therein, it being the intention of the Legislature not to make the other provisions of the act dependent upon the validity of said preference.
The term "civil service" of a city shall include all offices, positions, and employments, in which the officers or employés are paid by the city treasurer, either directly or through some official or agent, and all offices, positions, and employments, in or under institutions, departments, boards, or commissions, wherein the city, through any official or board or commission, has the exclusive right to select the officials and employés.
53 P.S. § 23431