UPDATE: Joseph Garcia received a lethal injection at the state penitentiary in Huntsville for the December 2000 shooting death of 29-year-old Irving police officer Aubrey Hawkins.

Joseph Garcia (TDCJ)

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HUNTSVILLE (CBSDFW.COM/AP) — Attorneys for a death row inmate who is scheduled to die Tuesday say he should be spared because he wasn’t the one who killed a North Texas police officer during a Christmas Eve robbery 18 years ago, it was other escaped inmates he was with.

Joseph Garcia, 47, is slated to die by lethal injection after 6 p.m. at state penitentiary in Huntsville. He was among the notorious “Texas 7” gang of inmates who escaped from a South Texas prison in December 2000 and then committed numerous robberies, including the one in which they shot 29-year-old Irving police Officer Aubrey Hawkins 11 times, killing him.

Hawkins had just finished Christmas Eve dinner with his family when he responded to the call about the robbery at a sporting goods store and was ambushed.

The escaped inmates were arrested a month later in Colorado, ending a six-week manhunt. One of them, Larry Harper, killed himself as officers closed in and the other six were convicted of killing Hawkins and sentenced to death. Garcia would be the fourth to be executed. The other two, Randy Halprin and Patrick Murphy, Jr., are on death row.

The “Texas 7” fugitives (top L-R) Joseph Garcia, Donald Newbury, George Rivas, Larry Harper, (bottom L-R) Patrick Murphy, Jr., Randy Halprin and Michael Rodriguez. (credit: TDCJ/AFP/Getty Images)

Garcia’s attorneys have asked the U.S. Supreme Court to stop his execution, arguing that he never fired his gun at Hawkins or intended to kill the officer. One of his lawyers, J. Stephen Cooper, said prosecutors didn’t have any information that showed his client was one of the shooters.

“He didn’t do anything violent or prepare or encourage anybody else to do anything violent,” Cooper said.

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Garcia was convicted under Texas’ law of parties, in which a person can be held responsible for another individual’s crime if he or she assisted or attempted to help in the commission of that crime.

Toby Shook, the lead prosecutor who handled Garcia’s case and those of the other five inmates, said that although authorities couldn’t narrow down which inmate used which gun to shoot Hawkins, the inmates acted as a team to commit the robbery and to kill the officer.

Shook said Garcia’s case is a clear example of why the law of parties is needed in certain cases.

“He was up to his ears in murder and mayhem out there. He was actively participating in everything,” said Shook, now a defense attorney in Dallas.

Shook said Garcia’s execution will be another step to getting closure for Hawkins’ family and law enforcement.

“Ultimately, we can finally close the book on them when the punishments are all completed,” he said.

Garcia was serving 50 years for a San Antonio-area murder when he and the other six inmates broke out of prison. He would be the 22nd inmate put to death this year in the U.S. and the 12th executed in Texas, which is the nation’s busiest capital punishment state.

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(© Copyright 2018 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)