While there is no evidence Fox committed a crime, Heckler said, his staff is investigating.
"There is a specific law for impersonating a police officer, but there is no such law for being a deputy prothonotary and issuing or serving a subpoena when you know there isn't a case," Heckler said.
"There are more general statutes which might well have been violated," he added.
The county's website has downloadable subpoena forms for lawyers and complainants to fill out to get signed and stamped at the Prothonotary's Office. The subpoena must be for a pending civil case, with the case number posted on the subpoena.
The subpoena "is invalid without the case number," Prothonotary Patricia Bachtle said.
Fox's subpoena had no case number because there was no civil case, Heckler said. Fox signed and stamped it and served it at Farm & Home Oil on Levittown Parkway, near where he had displayed signs for www.tullytownnews.com.
Fox is not authorized to serve subpoenas, Heckler said. He is authorized to sign and stamp them, said Bachtle, who declined to discuss the case further pending the district attorney's investigation.
She said Fox, who has worked in the Prothonotary's Office for seven years and has a salary of $44,616, remained on the job.
Fox declined to comment.
Fox filed a complaint about the missing signs Sept. 8, and Tullytown police consulted with Heckler's office. On Sept. 13, police told Fox they would not investigate his complaint because Heckler's office had determined it was not a criminal matter.
Fox responded that "he would handle the matter himself," a police report said.
The next day, he served the subpoena, but employees at Farm & Home Oil contacted police, who passed it along to Heckler's office.
Invalid subpoenas pop up occasionally, County Court Administrator Douglas Praul said.
The forms are downloaded by a lawyer or a person representing himself or herself, "but they usually don't fabricate an entire case," said Praul, who is not involved in the Fox case.
Contact Bill Reed at 215-801- 2964 or firstname.lastname@example.org, or follow on Twitter @breedbucks.