53 Pa.C.S. § 8921
(a) General rule.— Any information gained by a city of the first class as a result of a tax audit, tax return, tax report, investigation of tax liability, administrative hearing regarding tax liability or verification with respect to tax liability shall be confidential tax information. It shall be unlawful, except for official purposes or as provided by law, for an officer, employee or agent of a city of the first class to: