A group of MIT students have hired private detectives to investigate security at their natty neighbor Harvard after a drug dealer was murdered and dorm security was compromised on the Ivy League campus last month.

The MIT Crime Club hired the private eyes following the May 18 murder of Justin Cosby, 21, who police say dealt drugs to Harvard students and was shot to death at one of its residential houses.

One leader of the MIT group hopes the investigation brings safety improvements and better police communication with Harvard students.

“It’s about us giving them the ability to promote security without having to take the heat for it. We take the heat,” said 1987 MIT graduate James Herms, who described the MIT group as campus crimestoppers.

Most of the Crime Club’s members are MIT students, although Harvard students have joined in the past.

The investigation hit a bump last weekend when a husband-and-wife private detective team was arrested for snooping in Kirkland House, where the murder occurred.

Joe A., 46, and Elissa Cadillic, 37, a Boston Public library worker and a union official, were arrested Saturday and charged with trespassing, and breaking and entering. Their attorney, William Crowe, said the case is “baseless.”

The Cadillics, who live in Brighton, did not break the law, he said.

Joe Cadillic was hired by Simmons Agency, which in turn was hired by the Crime Club and an unamed individual to probe Harvard security lapses, said agency owner Bob Simmons.

“We just want the police to try and be more forthcoming with information . . . so the kids will know areas to stay away from,” said Simmons, citing Banks Street as one dangerous area where students have been robbed.

He said the individual who partnered with the club is not affiliated with Cosby or his accused killer, Jabrai Jordan Copney. The person has an interest in security, he said.

“We were asked to investigate the murder to see how often the victim had been on Harvard property, to determine if anyone at Harvard knew he was visiting the university and if Harvard had knowledge he was selling drugs there,” Simmons said.

A Harvard spokesman declined to comment.