The U.S. military has scheduled the execution of former Army psychiatrist Nidal Hasan for Dec. 3 at Fort Hood, Texas, using a firing squad — a method not used by the military since 1945. President Donald Trump approved the execution, Pentagon spokesperson Sean Parnell announced on social media Monday night. Army Secretary Adam Telle set the date and location in an order released Tuesday. The Pentagon has not publicly explained why it chose a firing squad or why it is moving ahead with the execution now. Hasan could seek to delay the proceedings by filing a habeas corpus petition in federal court, said Robin Maher, executive director of the Death Penalty Information Center. Presidential approval is a significant step, Maher said, but does not mean an execution is imminent. Ronald Gray, another soldier on military death row, remains incarcerated despite President George W. Bush approving his execution in 2008. Hasan was working as an Army psychiatrist in November 2009 when he opened fire at Fort Hood’s processing center, where troops were preparing to deploy to Afghanistan. He killed 13 people and wounded 32 before civilian security officers shot him. Hasan was left paralyzed from the waist down. At his 2013 trial, Hasan represented himself and acknowledged he was the shooter. A military jury convicted him on all counts and sentenced him to death. The Supreme Court rejected his final petition in 2025, ending the direct appeal process. Hasan is held at the U.S. Disciplinary Barracks at Fort Leavenworth, Kansas, along with the three other people on military death row. The military has not carried out an execution since 1961, when Private John Bennett was hanged. Its most recent firing-squad execution was that of Private Eddie Slovik in 1945, who was convicted of desertion during World War II. The military reinstated the death penalty in 1984 after a suspension, and lethal injection was designated as its standard method. Army regulations changed in 2023 to give the president discretion over the execution method. The timing comes as execution methods face renewed scrutiny following a failed lethal injection in Tennessee involving Christa Pike. Some death-penalty experts suggested the case may have influenced the decision to use a firing squad, though the administration has not said that was a factor. Corinna Lain, a law professor and author who studies capital punishment, said states have spent heavily on executions while still experiencing botched procedures. She said the question of whether firing squads are a better alternative remains unresolved. Firing squads have also drawn criticism: an autopsy after a South Carolina execution last year raised concerns that gunfire may have missed the prisoner’s heart and prolonged his death. Seven states now authorize firing squads, and the Justice Department made the method available for federal executions earlier this year following a Trump directive. At the same time, death sentences have fallen sharply over the past three decades, according to Death Penalty Information Center data, and public support for capital punishment is at a five-decade low, according to a 2025 Gallup poll cited by the center. Defense Secretary Pete Hegseth said last year he was committed to carrying out Hasan’s death sentence, arguing that victims and survivors deserved justice. Yale military-justice professor Eugene Fidell said the military’s long absence of executions makes the case especially consequential, and questioned whether announcing the decision on social media was an appropriate way to communicate it.