74 Pa.C.S. § 5702: Commencement of proceedings for summary offenses.

In cases where the alleged violation of this chapter is designated a summary offense, proceedings shall be instituted under applicable law within 30 days after the commission of the alleged violation. If the proceedings are instituted against a person prima facie guilty of an offense and it subsequently appears that another person was the violator, proceedings may be instituted against the other person within 30 days after his identity has been discovered.