Following are links to information on defamation laws in Pennsylvania. A person who has been defamed has one year from the date of first publication of the defamatory statement(s) to file suit.
From the Digital Media Law Project (2014):
https://www.dmlp.org/legal-guide/pennsylvania-defamation-law
From the Legal Clarity Organization:
https://legalclarity.org/defamation-of-character-in-pennsylvania/
As a note: Defamation is the communication of
false statements of fact that injure a reputation. A
complaint filed with the police about a crime, even if it names someone suspected of committing the crime, cannot form the basis of a defamation suit - unless it can be proven that the complaint was filed knowing the allegations were false at the time it was filed. Police complaints are covered by a “qualified immunity” to protect reporters of crimes from being sued over the content of their reports. The complaints themselves are neither true nor false. An investigation is required to determine the validity of a complaint.