TAMPA, Fla. — As an Army sniper in Iraq and Afghanistan, Gabriel Brown craved danger. Combat satisfied what he called his "adrenaline addiction."

When he returned home to Florida, nothing in civilian life provided the sense of invincibility that made combat so alluring and vital. The sniper was now a nursing student. There was a hole in his life, but he found a way to fill it: robbing banks.

He robbed with a military flair. On Feb. 5, 2013, Brown whipped out a gun and tossed an M83 military smoke grenade during a robbery of a TD Bank branch in Auburndale, Fla., that netted $19,000. It was his final crime in a two-week string of robberies that targeted banks, a cellphone store and an insurance company.

Brown was arrested the next day on federal charges that carry a mandatory minimum sentence of 32 years to life. He quickly confessed.

"It was extremely hard for me to find a way to go from being in highly threatening situations, risking my life every day, to sitting at home watching TV alone," he wrote later. "The adrenaline I got from committing robberies was some kind of weird addiction I so desperately needed to get myself out of this depressive state I was in."

Like thousands of other combat veterans, Brown was diagnosed with post-traumatic stress disorder. And like thousands of PTSD veterans seeking reduced sentences for crimes, he blamed the condition, in part, for his actions.

Increasingly, veterans across the U.S. have cited stress related to their combat experience as the reason for civilian misdeeds, a tactic that often reduces or even eliminates sentences for minor crimes, especially in special veterans' courts.

"It's a growing trend, with the stigma of PTSD largely eliminated and the condition more widely understood," said David Frakt, a law professor and Air Force Reserve military legal officer.

But blaming PTSD for serious felonies rarely succeeds, even for elite soldiers like Brown, 34, a decorated Green Beret with no previous criminal record. Courts are aware that most PTSD veterans manage not to commit serious crimes, said Victor Hansen, a law professor and former Army legal officer.

The result of Brown's plea for clemency was different — so different that Hansen and other legal experts could recall no case like it.

In a federal courtroom in downtown Tampa last month, Brown faced sentencing after pleading guilty and testifying against a fellow veteran, Robert McChristian, who was sentenced to 30 years in prison. He cut a sympathetic figure: a powerfully built war hero with a shaved head, military bearing, exemplary combat record and a powerful sense of remorse.

In the gallery was Maria Suarez, his ex-wife and mother of their two children, who divorced him after he signed up as a private security officer for CIA operatives in Pakistan when he left the Army. She dabbed at her eyes with a tissue. Beside Suarez was Brown's mother, a small woman fighting to hold back tears, and his stepfather, a thin, mustachioed Arkansas truck driver.

Brown's family believed PTSD drove him to crime after contributing to his alcohol and drug abuse, depression, nightmares and compulsive gambling. He wouldn't have been the first: A 2012 survey of 1,400 veterans diagnosed with PTSD found that 23% committed crimes, mostly nonviolent, after deployment, according to the Journal of Consulting and Clinical Psychology.

Family members said Brown's personality changed as he struggled to cope with civilian life after 10 years in the Army and four more in Pakistan.

"That wasn't my son — my baby boy. He was distant and angry and threw fits," said his mother, Debby Barrack, who signed for Brown to join the Army at 17.

"He'd never done anything like that, not my little brother. He's always been such a good man and good father," said his sister, Sandra.

Brown's ex-wife wept as she told the judge how Brown drove their children 16 hours to Arkansas every Christmas to visit his parents. Brown is their children's "superhero," she said; his criminal life was "completely out of character for him." He had refused previous treatment for his combat stress, she said, because "this was like a sign of weakness and he wanted to be the brave hero he was paid to be."

Brown had seemed to drag home a troubled life from Afghanistan and Pakistan. He suffered brain trauma from being knocked unconscious by a 50-caliber gun barrel in Afghanistan. He was diagnosed with depression and bipolar disorder. He gambled away $48,000 in a single night. Twice, he tried to commit suicide by taking Xanax or sleeping pills.

While in prison awaiting trial, Brown wrote letters of apology to every person he robbed, though no one had been injured.

"I want you to understand how sorry I am that I scared you," he wrote.

He also wrote about his years at war, during which he earned a Bronze Star for fighting through an ambush in Afghanistan to rescue comrades. Brown told of a young Afghan girl whose bloodied arm was hanging by a piece of skin after a U.S. military airstrike at Taliban positions. In an essay titled "Sniper," he described aiming his rifle at two insurgents and killing both.

Brown said he reluctantly followed orders to kill an Afghan man who stepped from his house with a rifle slung over his shoulder. "It is not easy to kill people, and if you have to kill someone you suspect is innocent just because you are ordered to do so, it is even worse," he wrote.

"This is a man who had no training other than how to kill," Brown's lawyer, Jose A. Baez, told U.S. District Judge James Moody. Baez screened an elaborate video presentation of Brown's military career, subtitled "Leave No Man Behind," the soldiers' creed.

Baez urged the court to consider the entire picture — the troubled soldier armed and in uniform, shown in one photo, the mixed-raced child growing up in tiny Waldo, Ark., shown in another. He asked the judge to "ration justice."

"We can't leave Gabriel Brown behind," he said.

A clinical psychologist, Scot Machlus, testified that Brown suffered from "sensation-seeking syndrome," prompting "reckless and self-destructive behavior." PTSD played "a very significant role" in Brown's criminal behavior, he said.

Brown said the robberies were proposed by McChristian, a convicted felon and marijuana-smoking buddy. He reluctantly agreed, Brown said, because he needed money after failing a nursing school course, which cost him his GI Bill payments. He was about to be evicted from his apartment.

Brown used a small silver Derringer pistol in some robberies, saying he thought it would be less threatening. But he used a more menacing Cobra .380-caliber handgun in others. Brown threatened a bank teller that he would come back for her if she put dye packs in the bags of money he stole.

His entire take was $20,199. Using surveillance video and a witness description from the cellphone robbery, police tracked down Brown's car and arrested him with the Cobra handgun and $15,665 in stolen bank cash the day after the Feb. 5 TD Bank robbery.

Brown later wrote that he was "rapidly spiraling downward, out of control." But "during the robberies I felt the same kind of adrenaline rush I felt when I was on missions."

At sentencing, the judge asked Brown whether he had anything to say. The former staff sergeant stood at attention. Between sobs, he apologized to those he robbed and to his family — especially his children. "And I'd like to apologize to my country. I love my country very much."

A prosecutor seemed impressed by the video presentation, calling it "very admirable." But he pointed out that Brown had had a role in 10 armed robberies, had threatened tellers and had pointed loaded guns at his victims. He asked for a 17 1/2-year sentence, a rare departure from the federal mandatory minimum.

Judge Moody called the case "certainly one of the most difficult cases I've ever had to fashion a sentence for." He told Brown his crimes were "extremely dangerous and violent." However, he said, they were "completely out of character."

Then the judge imposed the sentence: five years on each of the two charges, to be served concurrently. Reminded that the sentences must run consecutively, Moody reduced them further to 2 1/2 years on each count.

Brown buried his head in his arms, his shoulders heaving as he burst into tears. His mother and his ex-wife sobbed loudly. "Thank you, Lord," his mother said. Suarez bowed her head, grateful that the judge had granted Brown's request for in-prison drug abuse and PTSD treatment.

Moments after the ruling, Baez said the sentence may set a precedent. "This judge did a very brave thing. He looked at Gabriel Brown and saw the man — an absolute hero," he said.

Brown wiped his eyes, then winked and smiled at his family. "Thanks for coming," he whispered. "Love you."

As two U.S. marshals escorted Brown to prison in his blue inmate overalls, the judge looked down at the former sniper and said, "Good luck to you, Mr. Brown."

