The mother of a 21-year-old man who was fatally shot in a Harvard dormitory three years ago has filed a lawsuit against the University and three Lowell House officials claiming that Harvard’s negligence in allowing a drug dealer to live in Lowell for months led to the wrongful death of her son.

Jabrai Jordan Copney, who was convicted of the murder of Cambridge resident Justin D. C. D. Cosby in criminal court last year, lived with his girlfriend, a Harvard student, for most of the school year before the murder in May 2009.

B. Denise Cosby, the murder victim’s mother, filed a wrongful death suit last Friday against the University, Lowell Co-House Masters Dorothy A. Austin and Diana L. Eck, and chemistry and chemical biology lecturer Ryan M. Spoering, who was resident dean of Lowell at the time of the shooting.

The complaint alleges that the three Lowell House officials either “knowingly allowed Copney, a nonstudent, to live in the Lowell House for an extended period of time, in contravention of Harvard’s rules, and allowed him to have unfettered access to the House and the rest of Harvard’s campus,” or “negligently failed to detect Copney’s continuing, unauthorized presence.”

As a result of the University’s negligence, the complaint says, Copney was able to run “a criminal enterprise”—a pattern of holding Ivy League drug dealers at gunpoint for their marijuana.

Copney, who is originally from New York, had been living for most of the academic year with his girlfriend Brittany J. Smith, then a Harvard senior, in her Lowell House room when the Kirkland shooting occurred.

According to testimony in Copney’s murder trial last year, Copney and two other men, who had come from New York to conduct a drug robbery with him, invited Cosby, who sold marijuana to Harvard students, into the basement of Kirkland’s J-entryway with the intent of stealing marijuana from him at gunpoint. When Cosby refused to hand over the drugs, Copney shot him, prosecutors and witnesses said.

Earlier in the year, Copney and one of the two associates held up two other drug dealers—Yale students whom they had met at a party in Kirkland House during Harvard-Yale weekend—in an incident that was termed a “blueprint” for Cosby’s killing.

Copney was sentenced to life in prison for Cosby’s murder in April 2011.

Copney’s two associates, Jason F. Aquino and Blayn Jiggetts, both pleaded guilty to manslaughter charges and accepted shorter prison terms.

In September, Smith pleaded guilty to five charges connected to her role in hiding the murder weapon after the fact and protecting Copney. She was sentenced to three years in prison.

University spokesperson Kevin Galvin wrote in an emailed statement that the University will fight the suit.

“We recognize that the Cosby family has suffered a heart-rending loss, but there is no basis in law or fact to hold the University accountable for Justin Cosby’s death,” Galvin wrote. “He entered Harvard property that day for the sole purpose of selling a large quantity of marijuana to people unaffiliated with the University, and one of them shot him. We will vigorously defend against this lawsuit.”

In a phone interview with The Crimson, Denise Cosby’s lawyers Isaac H. Peres and Dennis A. Benzan said that Denise Cosby had waited for the criminal trials to conclude and for more information about the murder to be revealed before suing the University.

“She felt that the time was right,” Benzan said. [The criminal proceedings have] taken a tremendous toll on her, but she’s been able to regroup over the last few months and move forward with this suit.”