BROOKLYN — A Brooklyn judge refused to release "Grid Kid" killer John Giuca Tuesday, even though four judges in the appellate division voted unanimously to vacate the conviction and grant him a new trial.

The appellate division had ordered another trial in the 2003 murder of 19-year-old Fairfield University football star Mark Fisher. It accepted the defense arguments that a lead prosecutor in the first case gave special treatment to a key witness who had a heroin addiction and pending jail time.

Fisher was killed in October 2003, after going to Manhattan for the first time ever to meet college friends at a bar.

The teen missed his last train home and ended up at John Giuca’s house party in Ditmas Park at 5 a.m. A trial witness said Giuca was mad that Fisher sat on a table in his house, thought he was being disrespected, and gave friend Antonio Russo a gun to “show Mark Fisher ‘what’s up.’”

It took a year for police and the Brooklyn District Attorney to round up witnesses.

A witness said Giuca ordered Russo to shoot Fisher, part of a tough-guy routine tied to their “Ghetto Mafia” gang.

The outcome of the original case had always troubled Mark Fisher’s father, who sat stoically in court Tuesday. He’s always believed other people were present at the shooting scene.

PIX11 spoke to several residents of Argyle Road in 2014. They had heard five or six gunshots at about 6:40 a.m. on Oct. 12, 2003.

One of them, Michel Swornik, said he heard shots, a van door open and then several voices, including a female’s voice. He went outside to find Mark Fisher dead in his driveway.

On Tuesday, the defense spoke of two witnesses from the first trial who went to the party on Oct. 12 and claimed they had stayed up the block from the shooting scene on Argyle Road, hearing nothing. The van involved in the shooting was never found.

“The fact is, a case that’s going to be centered on Albert Cleary and Angel DiPietro is a loser,” defense attorney Mark Bederow told Judge Danny Chun. “The case against him has been reduced to rubble.”

Cleary and DiPietro said they were sleeping at Cleary’s house up the block at the time of the shooting.

DiPietro later became an assistant district attorney in the Brooklyn DA’s office.

The District Attorney’s office could have chosen to recommend that Giuca, now 33, be released after serving more than 13 years in prison. Instead, it is challenging the appellate division decision in the Court of Appeals.

“At this point, I find no reason to release this defendant nor grant bail in this case,” said Judge Danny Chun.

Chun ordered a new trial for May 1.

Giuca looked sickly in court.

As he was led back to his cell on Rikers Island, his mother Doreen Giuliano yelled out in court, “I love you, John.”