WASHINGTON (CNS) — “The Phantom,” a new documentary on a capital murder case gone awry, is being released in theaters amid a Catholic Mobilizing Network campaign asking President Joe Biden to abolish the federal death penalty.

The online petition had already garnered more than 9,000 virtual signatures by June 23. A day earlier, Attorney General Merrick Garland announced an official review of the federal death penalty.

“Our shared Catholic faith compels us to ‘work with determination for (capital punishment’s) abolition worldwide,'” the petition tells Biden, quoting the Catechism of the Catholic Church. “Please act swiftly to dismantle the fatally flawed federal death penalty system and uphold the sacred dignity of every person.”

Although it was not a federal trial, the murder case examined in “The Phantom” shows that an innocent man might have been executed for the crime.

Wanda Lopez, a convenience store clerk in Corpus Christi, Texas, was stabbed to death in 1983 as she was calling 911 to report a man with a knife outside the gas station where she worked.

After a 45-minute manhunt, Carlos DeLuna, who had a criminal record, was discovered shirtless under a truck. Police arrested him, and other officers who had been pursuing another man peeled off once news of DeLuna’s arrest crackled over police radios.

DeLuna protested his innocence, telling police it was another Carlos — Carlos Hernandez — who had slain Lopez, a young single mother. At one point, 10 different men named Carlos Hernandez, each of whom had their own run-ins with the law, were paraded for a lineup. DeLuna said none of them was the Carlos Hernandez he had seen.

Prosecutors figured this unfound Hernandez was a “phantom,” someone who didn’t exist and was being blamed for a crime. Against his lawyer’s advice, DeLuna took the stand in his own defense to protest his innocence. It didn’t work. He was found guilty of murder and sentenced to death, dying in the execution chamber in 1989 in Huntsville, Texas.

In 2004, 15 years after DeLuna’s execution, a team from Columbia University’s law school looked more deeply into the case. The initial investigator needed only an hour to find DeLuna’s Carlos Hernandez, who had been arrested for violent crimes — including with knives — but managed to avoid long sentences.

A clip in “The Phantom” of George W. Bush, then Texas’ governor, shows him saying no innocent person had ever been executed in the state. Supreme Court Justice Antonin Scalia, in a 2006 capital case from Kansas, expressed doubts any innocent person had been executed. If any had been, he said, death penalty opponents would have “shouted from the rooftops” the innocent’s name.

“It does happen and has happened,” said Jim Liebman, the Columbia law professor whose team of law students unraveled the case.

“Phantom” director Patrick Forbes said during a June 22 phone interview with Catholic News Service from his home in London that he got many of the principals from 1983 — the prosecutor, the defense attorney, a witness and a television reporter on her first big story — into an empty courtroom to re-create testimony. He didn’t need to refresh anybody’s memory.

“They needed no prompting from me,” Forbes said. “The trial and the case were such a seminal moment in their life.”

“We investigated it throughout all of 2005 and into 2006, partway through 2006 we felt like we had enough to turn it over to the Chicago Tribune and take a look at it,” Liebman told CNS in a June 18 phone interview. “They published a three-part series on the case in 2006.”

Royalties from a book Liebman co-wrote on the case were donated to the Gulf Region Advocacy Center in Houston. Director Patrick Forbes adapted the book to make “The Phantom.”

The documentary made its debut in mid-June at the Tribeca Film Festival in New York. It will run in selected theaters across the United States beginning July 2.

Forbes said he was gratified at the reception the film got at Tribeca. “Actually, I was absolutely thrilled. Some of the reviews were fantastic and get the point,” he told CNS. “I thought that people got the point of the movie and why it had been made. And if that reception is repeated on a national scale, it’ll be fantastic. And I hope it is.”

Liebman, too, enjoyed the movie. “They took the case and the basic story had been laid out, and essentially reinvestigated it themselves and found out some other information and found a number of people willing to speak to them who were not willing to speak to us,” he said. “As a result, the information became even clearer.”

What still weighs on Forbes’ mind, though, is the possibility of an executive order banning the death penalty in federal cases. “Will Biden sign it?” he asked.