Newark police officer Joseph Macchia was drinking off-duty at a Union Township bar when he got into a fight, drew his service weapon and shot a man to death two years ago.

On Tuesday, court officers led him to jail after a Union County jury convicted the 36-year-old of reckless manslaughter in the shooting death of Michael Gaffney.

"He went out in cuffs, just like he should have," said Gaffney's mother, Judy Valdes, shortly after the verdict. "He's behind bars where he belongs. ... Justice has prevailed."

Michael Gaffney, 37, of Piscataway, was shot to death May 13, 2016.

Gaffney, 37, of Piscataway, died on May 13, 2016 after being shot by Macchia outside Paddy's Place bar in Union. He was the father of a 13-year-old girl.

Gaffney and Macchia were acquaintances and got into a verbal altercation in the bar.

Outside the bar, the verbal dispute turned physical and ended after several minutes, authorities said at the time. But moments later, the fight started up again and Macchia pulled out his gun and fatally shot Gaffney. A 911 caller reported hearing five shots.

Macchia, an 11-year veteran of the police department, was not arrested but did have a blood alcohol test with a result of .13. He was indicted on a manslaughter charge the following November, and was released on bail. He has been on unpaid leave since his indictment.

"As much as it hurt, I'm glad we went through this and he'll never be a cop again," Valdes said after the verdict. "He's a criminal."

She said Gaffney's daughter, who is now 16, wept in court after hearing the guilty verdict. The trial and the waiting has been hard on the family and friends who lost Gaffney, she said.

"It sucked the life out of me for five weeks," she said.

update: the officer has been convicted!! This is my son Michael P Gaffney, my world. His life was senselessly and... Posted by Justice for Gaffney on Friday, September 29, 2017

Now that the trial is over, Valdes said she can focus their fight on creating legislation to make it a crime for a police officer to drink and carry a firearm.

An online petition in support of "Gaffney's Law" said it should be illegal for officers to carry a gun into a bar or anywhere they plan to drink. It was signed by nearly 6,000 people, but no legislator has drafted the bill.

"Alcohol and guns don't mix. If you cannot drive under the influence, it only makes sense you shouldn't carry under the influence," the petition said. "Michael Gaffney was not armed, he had no weapons. The officer involved knew Michael, they had been to parties and BBQ's together. Yes, they were both drinking, yes, a fight ensued, but never should an intoxicated officer with a gun solve drunken anger with his service weapon."

Acting Union County Prosecutor Michael A. Monahan echoed the sentiment in a statement Wednesday, calling the case a "prime example of the tragic and senseless consequences that often arise when alcohol and firearms align."

After having his bail revoked, Macchia will remain in jail until his sentencing July 27, according to the prosecutor's office. Second-degree crimes including manslaughter carry a maximum penalty of 10 years in prison.

Rebecca Everett may be reached at reverett@njadvancemedia.com. Follow her on Twitter @rebeccajeverett. Find NJ.com on Facebook.

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