WASHINGTON – The American Civil Liberties Union on Tuesday blasted President Donald Trump's decision to pardon a former Army first lieutenant convicted of killing an Iraqi prisoner, saying the move amounted to a "presidential endorsement of a murder."

Trump granted the pardon late Monday to Michael Behenna, an Oklahoma man who was sentenced to 15 years in 2009 for killing Ali Mansur Mohamed, a suspected al Qaeda operative who was stripped naked for questioning before being shot.

"This pardon is a presidential endorsement of a murder that violated the military's own code of justice," said Hina Shamsi, director of the ACLU's National Security Project. "Trump, as commander-in-chief, and top military leaders should prevent war crimes, not endorse or excuse them."

Behenna had long argued he acted in self-defense. Oklahoma Attorney General Mike Hunter had petitioned the White House for the pardon.

“Mr. Behenna’s case has attracted broad support from the military, Oklahoma elected officials, and the public,” White House press secretary Sarah Sanders said in a statement Monday. “While serving his sentence, Mr. Behenna was a model prisoner.”

Behenna was paroled in 2014 after serving less than five years of his sentence.

Mansur was questioned in connection with a roadside bomb that killed two soldiers.

More:Can Trump really do that? The presidential pardon power, explained

Trump has frequently used his clemency power to make political statements, pardoning conservative commentator Dinesh D'Souza, former Arizona sheriff Joe Arpaio, and former Bush White House aide Scooter Libby, among others. That's hardly unprecedented, but previous presidents have tended to grant their most controversial pardons in their final months in office. Trump has done so early in his presidency.

Contributing: Gregory Korte

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