72 Pa. Stat. § 5511.15
It shall not be lawful for any county treasurer, county commissioner or any tax collector, nor for any other person, on his or their behalf, to receive payment or give any receipt for the payment of any taxes that have not been duly assessed and returns of said assessment made according to law, nor shall any such treasurer, commissioner or tax collector, or other person on his or their behalf, receive payment or give any receipt for the payment of any taxes, from the collection of which the tax collector has been exonerated according to law. But where the tax collector has been so exonerated, such taxes shall remain payable to the taxing district. Except as hereinafter otherwise provided, it shall not be lawful for any county commissioner, or for any other person on his behalf, to add any name to the duplicate return or list of taxables made or furnished by the assessor or assistant assessors of any township, ward or district.
72 P.S. § 5511.15