Officer Geoffrey Breitkopf was mistakenly shot and killed by an MTA officer while responding to a scene in March 2011.
The police union unveiled a bronze plaque dedicated to Officer Breitkopf at the corner of Clark Boulevard and Front Street in Massapequa Park.
The plaque was made by the members of local Boy Scout troops.
The Breitkopf family, many members of the Nassau County Police Department, the departmental Ceremonial Unit, Color Guard and Pipe Band were all in attendance.
