Two men accused of a May 2009 killing in a Harvard dorm allegedly got their start robbing Yalies.

Jabrai Jordan Copney — who allegedly shot and killed Justin Cosby in a Harvard dorm after what investigators deemed a failed “drug rip” — and his alleged accomplice Blayn Jiggetts were accused in Middlesex Superior Court documents of stealing a large supply of marijuana from two Yale undergraduates in New York City in 2008, the Harvard Crimson reported. The report also said that Jiggetts admitted to the Middlesex District Attorney’s Office that this robbery served as a blueprint for the Harvard incident.

Copney allegedly robbed Jules Bolton ’09 and Alexander T. King ’09 at gunpoint after telling him that he would buy $14,000 worth of marijuana. Bolton told investigators that Copney fled with the drugs and his and King’s IDs.

According to the Crimson, Bolton told an investigator in September 2009 that he and King first met Copney in Cambridge during the 2008 Harvard-Yale football game. Bolton and Copney allegedly arranged the drug deal and agreed to meet at a Starbucks near Grand Central Station.

After claiming to have left his money at home, Copney led the two Yale students to a Harlem apartment, the Crimson reported from court documents it obtained. Eventually, Jiggetts brandished a pistol, and Copney told Bolton to hand over the marijuana. The pair allegedly also stole Bolton’s driver’s license and King’s Yale ID.

The robbery served as a model for the pair’s attempted robbery in May 2009.

In that incident, Copney allegedly shot Cosby, who was not a Harvard student, in the J entryway of Kirkland House. Court documents allege that Cosby believed the men wanted to buy marijuana from him, while Copney, Jiggets and another alleged accomplice always intended to rob him.

Jiggets plans to plead guilty to manslaughter — a reduction from the original murder charge — while Copney is set to go to trial for murder on April 4 in Middlesex Superior Court.