In the four decades since the city formed the Knapp Commission to investigate sweeping charges of corruption in the New York Police Department, Frank Serpico, the police officer whose complaints led to the commission, has had no real contact with city or police officials.
For most of the past few years, Mr. Serpico has been living in a remote, single-room cabin in upstate New York.
But on Friday, Mr. Serpico, 77, opened his post office box in Stuyvesant, N.Y., to find a subpoena that will pull him into another whistle-blowing scandal involving the New York Police Department.
âI thought it was my Medal of Honor certificate, which Iâve been requesting for years,â said Mr. Serpico, who was awarded the medal after being shot in 1971 during a drug arrest in a Brooklyn building in which fellow officers did not provide immediate backup or medical help.
Instead the letter ordered him to turn over any documents or materials he might possess related to the trial of a city police officer, Adrian Schoolcraft, 38, who is suing the city in connection with an episode in 2009 that resulted in Mr. Schoolcraft being forcibly hospitalized and suspended from the force.
Mr. Schoolcraft, an officer in the 81st Precinct in Bedford-Stuyvesant, Brooklyn, secretly recorded roll calls in the station house, which he said demonstrated that commanders were telling officers to downgrade reported crimes, to reduce the rate of violent crime in the precinct. After speaking publicly about this, Mr. Schoolcraft was taken from his Queens apartment and transported to a psychiatric ward at Jamaica Hospital and kept there for six days.
Mr. Serpico, who also once worked in the 81st Precinct, said he had given numerous news interviews since 2010 supporting Mr. Schoolcraft and comparing the younger officerâs case to his own. He said he had personally assisted Mr. Schoolcraft - who moved upstate and has gone through shaky emotional periods â" both in person and on the phone.
âI tried to help him out and support him because I thought his case was legit,â said Mr. Serpico, adding that he has also assisted Mr. Schoolcraftâs legal team âon how the N.Y.P.D. treats whistle-blowers.â
The cityâs Law Department confirmed that Mr. Serpico had been served with a subpoena as the city defends itself against Mr. Schoolcraftâs lawsuit.
âBased on reported comments by Mr. Serpico to media outlets, we have reason to believe that he may have information relevant to Adrian Schoolcraftâs lawsuit,ââ said Suzanna Publicker Mettham, a city lawyer. âAs he is not a party, a subpoena was recently served requesting any relevant documents in his possession.â
A lawyer for Mr. Schoolcraft did not return telephone calls.
The cityâs subpoena, in an odd mistake, identified Mr. Serpico at one point as Mr. Schoolcraftâs father.
âI guess they think I adopted him,â Mr. Serpico said.
He said he had no materials to turn over relating to Mr. Schoolcraft and added that he had planned to attend the trial anyway. While the subpoena did not order him to testify, both Mr. Serpico and his lawyer expect to be called to the stand - which he says will surely not help the Police Departmentâs case.
âThey were never known for their genius,â Mr. Serpico said.
âItâll be fun â" Iâm looking forward to giving my opinion,â he said, then sighed and added, âForty years later, the beat goes on.â
This post has been revised to reflect the following correction:
Correction: August 6, 2013
An earlier version of this article incorrectly referred to a subpoena issued to Mr. Serpico. He was ordered to turn over any documents or materials he might possess. He was not ordered to testify.