A former Mattapan man was sentenced to life in prison today following his admission to the 1995 murder of Zandera Sullivan in a crime of deadly domestic violence, Suffolk County District Attorney Daniel F. Conley said.

PATRICK ANTHONY BROWN (D.O.B. 9/12/73), also known as DERRICK MALLOY, pleaded guilty yesterday to the crimes of second-degree murder and armed home invasion as his trial was scheduled to begin in Suffolk Superior Court.

In a hearing yesterday morning, Brown admitted to the May 29, 1995, incident, which claimed Sullivan’s life at his girlfriend’s Seaver Street home. That woman had ended her romantic relationship with Brown a few months earlier. Today, Judge Judith Fabrican imposed the mandatory sentence for murder two, life with the possibility of parole after 15 years, along with a two-year probationary term.

Brown, a Jamaican national, will be deported from the United States if he is ever released from prison.

Had Brown’s case proceeded to trial, Assistant District Attorney Gretchen Lundgren of the DA’s Homicide Unit would have introduced evidence and testimony proving that Brown went to his former girlfriend’s Seaver Street apartment building, walked up to her fourth floor apartment, and knocked on the door, asking to be let in. When she did not let him in, evidence would have shown, Brown went to the back door of the apartment, forced his way in, and made his way to her bedroom, where he encountered her and Sullivan.

The evidence would have shown that Brown drew a knife from his waistband, chased Sullivan from the apartment, and stabbed him to death. Sullivan was found in the apartment building vestibule a short time later suffering from fatal injuries to his carotid artery and jugular vein.

Shortly after the fatal stabbing, investigators obtained a warrant charging Brown with murder. Brown left the United States before he could be arrested. In the 15 years that followed, the Boston Police Department’s Fugitive Unit, its Cold Case Squad, the U.S. Marshals Service, and a series of Suffolk homicide prosecutors worked relentlessly to track Brown’s flight to Jamaica and several Central American countries. They were aided in 2009 by the television program America’s Most Wanted.

Those efforts led investigators to Belize early last year, and Brown was taken into custody in that nation on Feb. 9, 2010.

Catherine Rodriguez was the DA’s assigned victim-witness advocate. Brown is represented by attorney Scott Curtis.