The Blue Templar was a fraternal organization in the New York City Police Department. It was originally created for the purpose of policing the police, after the Serpico and Knapp Commissions were formed to investigate corruption in the NYPD during the 1970s.
The fraternal organization's goal of policing the police was abandoned after many of the original members left. The remaining members became corrupt themselves. The Blue Templar became involved in various criminal enterprises. One of their criminal enterprises involved drug busts. Members of the Blue Templar would kill all witnesses in a drug bust and steal their drug money to distribute among themselves.
The Blue Templar was willing to murder fellow NYPD officers who tried to expose them, as they did with Joseph Reagan. The Blue Templar attempted to murder his younger brother, Jameson Reagan as well. After their attempt on Jamie's life, the Reagan family, along with a few friends in the NYPD, conducted an operation together to bring down the Blue Templar.
In The Blue Templar, all of the fraternal organization's members are tracked down to a pub through Sonny Malevsky, who was unaware he was being tracked. As all of the fraternal organization's members are about to be arrested, Francis Reagan asks all of the members which one of them killed his son, Joseph Reagan. Sonny Malevsky confesses to murdering Joe and commits suicide after doing so. After the arrest of all the members of the Blue Templar, the fraternal organization is presumed to be defunct.
The Blue Templar takes on the role of being season one's main antagonist.