One of four young men charged in the April 2010 murder of gay D.C. middle school principal Brian Betts was shot to death on Sept. 19 by a man he attempted to rob at gunpoint in the victim’s Southeast Washington apartment, according to D.C. police.

Joel Johnson, 21, died in the apartment from a single gunshot wound to the head 15 months after he was released from prison upon his completion of an 18-month sentence in connection with Betts’ murder.

Montgomery County prosecutors allowed Johnson to plead guilty in 2011 to accessory after the fact, rather than murder, because he wasn’t the one who shot Betts and he cooperated with police and prosecutors.

D.C. police said Johnson and Jaren Holley, 21, each in possession of a handgun, approached a male victim as he was about to enter his apartment on the 4200 block of 1st Street, S.E., about 8:30 p.m. on Sept. 19.

In a statement, police said Johnson and Holley forced their way into the victim’s third floor apartment where the victim and a woman, who was also present in the apartment, lived. The police statement says investigators believe Johnson and Holley were planning to rob the victim.

Once inside, a struggle broke out between Johnson and the man he and Holley attempted to rob, the police statement says.

“During the course of the struggle, the decedent was fatally shot. The other suspect fled the scene,” the statement says.

Members of the D.C. Department of Fire and Emergency Medical Services responded to the scene and determined that Johnson showed no signs of life, according to the statement. It says Johnson was pronounced dead a short time later by a member of the Office of the Chief Medical Examiner.

Police said they apprehended Holley on Sept. 24 and charged him with first-degree burglary while armed.

D.C. police homicide detectives, who were assigned to investigate the case, had not filed any charges against the man who shot Johnson in the apartment. One police source said the investigation would likely determine that the man acted in self-defense.

On the day of the incident, D.C. police identified the dead man as Joel Johnson but didn’t immediately disclose that he was the same Joel Johnson implicated in the Betts murder case. That confirmation came from a spokesperson for the Montgomery County State’s Attorney’s office.

The spokesperson, Ramon Korionoff, told the Blade on Friday that Johnson’s cooperation with police and prosecutors helped authorities obtain a guilty plea of felony first-degree murder from Alante Saunders, the then 19-year-old youth that prosecutors say shot Betts to death inside the bedroom of the popular principal’s Silver Spring, Md., house on April 15, 2010. A judge later sentenced Saunders to 40 years in prison in connection with the Betts murder.

In the weeks following Betts’ murder, Montgomery County police and prosecutors disclosed that Saunders met Betts through a sex chat line that catered to gay men. Police said Saunders contacted Betts through the chat line and expressed an interest in getting together with Betts.

Betts, 42, apparently invited Saunders to his house, police said. As part of a plan to rob Betts, Saunders, Johnson and two others – Deontra Gray and Shariff Lancaster, both 19 — drove to Betts’ house. Prosecutors said Johnson was in the house when Saunders fatally shot Betts in what police described as a “robbery that went bad.”

Police apprehended all four men by tracing their whereabouts when they began making purchases with a credit card they stole from Betts’s houses.

Korionoff said Johnson was sentenced to five years in prison but a judge suspended all but 18 months of the sentence at the recommendation of prosecutors, who persuaded Johnson to plead guilty to the lesser charge as part of a plea bargain arrangement.

Betts had served as principal of D.C.’s Shaw Middle School at the time of his death. D.C. public school officials, who expressed shock and sadness upon learning of his death, described him as a highly acclaimed educator and innovative principal credited with boosting the academic achievement of his school’s students.

On the day Saunders was sentenced to the 40-year prison term an attorney representing Betts’ parents announced that the parents were calling on the U.S. Justice Department to investigate whether Betts’ murder should be classified as an anti-gay hate crime.

In a news conference at the courthouse where Saunders was sentenced, attorney Gloria Allred, who is well known for taking on high-profile celebrity cases, said Betts’ family retained her to explore whether Betts’ murder should be prosecuted under the Matthew Shepard and James Byrd Hate Crimes Prevention Act.

“Brian was a gay man and we believe an investigation should be opened under that law to determine whether a hate crime has or has not been committed by defendant Saunders and if it has whether it is appropriate to proceed with a federal prosecution under that law,” Allred said.

Montgomery County State’s Attorney John McCarthy told reporters at the courthouse that day that his office investigated the possibility that Betts’ murder was a hate crime and could not find evidence to substantiate a hate related motive in the case.

“If we had seen evidence of a hate crime, we would have charged it,” he said.

The Justice Department declined to become involved in the case.

Last week, the Betts family released a statement on Johnson’s death.

“We are deeply saddened that after Joel Johnson was given a second chance to become a productive member of society that he chose to continue to follow a path of crime and self-destruction which ultimately resulted in his death,” the statement says. “The loss of our family member, Brian K. Betts, a beloved educator and inspirational member of the community, has left a void for those who had the privilege to know him that will remain forever. Our sympathy is with the Johnson family at this time.”