The American Civil Liberties Union joined gay rights groups and civic and religious leaders today in calling for a thorough — and independent — investigation into the shooting death of Atlanta CEO DeFarra Gaymon by an Essex County sheriff’s officer.

“What we have here is a situation where an unarmed citizen ends up dead as a result of what would have been a minor crime,” said Deborah Jacobs, executive director for the ACLU-NJ. “Considering the seriousness of the incident and many unanswered questions, this investigation demands the legitimacy that only an external review can provide.”

The ACLU and Garden State Equality, the state’s leading gay rights organization, filed requests with Essex County law enforcement officials asking for specific documents relating to the shooting last Friday evening of Gaymon during a sweep of alleged homosexual activity in Newark’s Branch Brook Park.

“We make no assumption as to the sexual orientation of the victim. Nor do we condone lewdness, but any sting operation targeting gay men or LGBT people specifically, or anyone perceived as such, is unconscionable — and as we strongly believe, illegal,” Steven Goldstein, chair of Garden State Equality, said in a letter to Acting Essex County Prosecutor Robert Laurino.

One of Fonturo’s officers, an eight-year veteran of the department who has not been identified because he works undercover, is responsible for the single shot at closed range that killed Gayman.

Gaymon, 48, a father of four who was CEO of the Credit Union of Atlanta, was in New Jersey for his Montclair High School 30th class reunion when he encountered the undercover cop just before 6 p.m. Friday in Branch Brook Park.

According to a statement issued by Laurino four days later, two sheriff’s detectives were investigating complaints of people engaging in sexual acts in public. The police had already arrested one man when one of the officers realized he lost his handcuffs and went back to look for them, Laurino said.

He was approached by Gaymon who “engaged in a sexual act at the time,” Laurino said. When the officer pulled his badge, Gaymon “appeared to panic, assaulted the police officer and fled,” Laurino said. The officer pursued Gaymon who refused to stop and “repeatedly threatened to kill the officer,” authorities said. At the edge of a pond, the men grappled, Gaymon allegedly reached into his pocket and the officer shot him in the stomach. Gaymon was taken to University Hospital in Newark, where he died several hours later.

A key question asked by all groups involved was why the officer pulled his gun for what Jacobs at the ACLU called “basically a misdemeanor for which you normally get a fine.”

Garden State Equality and Gaymon’s family in Georgia — who called the statements by the prosecutor “blatant lies” — have called for a federal investigation into the shooting. The ACLU demanded the matter be referred to the state Attorney General’s Shooting Response Team.

Asked about the requests, Laurino’s spokeswoman, Katherine Carter, said only, “Right now, the Essex Prosecutor’s Office is in charge of this investigation.”