A St. Paul man pleaded guilty Monday to his role in a 2012 gang-related murder and agreed to testify against his co-conspirator in a trial that starts this week.

Juan E. Martinez, 23, pleaded guilty in Ramsey County District Court to one count of aiding and abetting a crime committed for the benefit of a gang, second-degree murder, in the death of Leonard Christian Sr., 56. As part of Martinez's plea deal, nine other counts against him will be dismissed, including aiding and abetting first-degree murder.

Eight other charges against Martinez, including aiding and abetting second-degree attempted murder, from a March 28 shooting that occurred days before Christian was killed, will also be dismissed.

Martinez's plea agreement calls for a 17½-year prison term. He is scheduled to be sentenced on June 19.

Martinez also agreed to testify in the case against Desean L. Thomas, whose trial began Monday with jury selection. Thomas, 23, is charged with 10 counts in Christian's death.

Authorities allege that Martinez and Thomas, members of the Hustle Made Mafia gang, and a third man shot at Christian's house in the 1000 block of W. Central Avenue on March 30, 2012, to retaliate against the Gotta Havit gang. Christian's son may have been the intended target.

Under questioning by Assistant Ramsey County Attorney David Miller, Martinez said that the trio went to Christian's house because, "Little Lenny Christian was staying there."

Miller asked Martinez what their plan was.

"Just gonna shoot it up," said Martinez.

Martinez testified that Thomas knocked on the back door and began firing, prompting him and the third man to shoot at the side of the house.

Martinez's testimony and the sealed indictments don't specify whose shots killed Christian, but Martinez's attorney, John Chitwood, said that testimony at Thomas' trial would show that Thomas fired the fatal shot.

"[Martinez's] presence was there, but his involvement was very minimal," Chitwood said.

The indictments don't address motive, and testimony Monday only noted that it was part of ongoing strife between the gangs, which both emerged from the Selby Siders gang.

Martinez also testified that he, Thomas and the third man were involved in two gang-related shootings leading up to Christian's murder.

The March 28 case against Martinez was dismissed. He was convicted in a March 29 shooting, and is serving four years in prison.

Thomas remains charged in the March 28 case. He is also charged in Dakota County District Court in connection with an August 2014 shooting that wounded a man.

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