BATON ROUGE, Louisiana — Hours before a Louisiana man is scheduled to be put to death Tuesday evening, his attorneys were hoping for a last-minute court ruling to halt the state’s first execution by nitrogen gas.

Louisiana plans to use the new method to put Jessie Hoffman Jr., 46, to death Tuesday evening in the state’s first execution in 15 years. Nitrogen gas has been used just four times to execute a person in the United States – all in Alabama, the only other state with a protocol for the method.

Hoffman’s lawyers say the method is unconstitutional, violating the Eighth Amendment’s prohibition on cruel and unusual punishment. They also say it infringes on Hoffman’s freedom to practice religion, specifically his Buddhist breathing and meditation in the moments leading up to death.

Louisiana officials maintain that the method, which deprives a person of oxygen, is painless. They say it is past time for the state to deliver justice promised to victims’ families after a decade and a half hiatus – a pause brought about partly by an inability to secure lethal injection drugs.

Attorney General Liz Murrill says that she expects at least four people on Louisiana’s death row to be executed this year.

Murrill said that she expected the execution to go forward as planned and that “justice will finally be served.” Hoffman was convicted of the 1996 murder of a 28-year-old advertising executive, Mary “Molly” Elliott, in New Orleans. At the time of the crime, he was 18.

After court battles earlier this month, attorneys for Hoffman are turning to the U.S. Supreme Court in a bid to halt the planned execution. However, the court declined to intervene in the nation’s first nitrogen hypoxia execution in 2024.

On Monday, Hoffman’s attorneys filed several challenges in state and federal courts in a last-ditch effort to spare him.

At a hearing Tuesday morning, 19th Judicial District Court Judge Richard “Chip” Moore declined to stop the execution. He agreed with state lawyers who argued that the man’s religion-based arguments fell under the jurisdiction of a federal judge who had already ruled on them, according to local news outlets.

Under Louisiana protocol, which is nearly identical to Alabama’s, Hoffman is to be strapped to a gurney and have a full-face respirator mask – similar to what is used by painters and sandblasters – fitted tightly on him. Pure nitrogen gas is then to be pumped into the mask, forcing him to breathe it in and depriving him of the oxygen needed to maintain bodily functions.

The nitrogen gas is to be administered for at least 15 minutes or five minutes after his heart rate reaches a flatline indication on the EKG, whichever is longer.

Each inmate put to death using nitrogen in Alabama has appeared to shake and gasp to varying degrees during their executions, according to media witnesses, including a reporter from The Associated Press. The reactions are involuntary movements associated with oxygen deprivation, state officials have said.

Currently, four states – Alabama, Louisiana, Mississippi and Oklahoma – specifically authorize execution by nitrogen hypoxia, according to records compiled by the Death Penalty Information Center.

Alabama first used the lethal gas to put Kenneth Eugene Smith to death last year, marking the first time a new method had been used in the U.S. since lethal injection was introduced in 1982.

In an effort to resume executions, Louisiana’s GOP-dominated Legislature expanded the state’s approved death penalty methods last year to include nitrogen hypoxia and electrocution. Lethal injection was already in place.

Over recent decades, the number of executions nationally has declined sharply amid legal battles, a shortage of lethal injection drugs, and waning public support for capital punishment. That has led a majority of states to either abolish or pause carrying out the death penalty.

Hoffman is scheduled to be the seventh person put to death in the country this year.