Pennsylvania Statutes Title 43 P.S. Labor § 1101.401. Employe rights

It shall be lawful for public employes to organize, form, join or assist in employe organizations or to engage in lawful concerted activities for the purpose of collective bargaining or other mutual aid and protection or to bargain collectively through representatives of their own free choice and such employes shall also have the right to refrain from any or all such activities, except as may be required pursuant to a maintenance of membership provision in a collective bargaining agreement.