"He was there to find the insurgents and bring them in, get them off the streets," said his mother, Fran Boyle.
Back home in Long Island, Sgt. Boyle's mother recalls how for five years, she counted every single day her son spent fighting insurgents:
"I'd be thinking I was going to get that phone call or that knock at the door telling me my son was dead or worse, captured. So it was very intense, but he got through it. He came back in one piece and we were all so proud of him," she said.
But in one night of drinking with his buddies at this bar outside Ft. Bragg North Carolina, Sgt. Boyle would go from a hero to criminal.
According to military documents, one of Boyle's friends, Private First-Class Luke Brown became drunk and belligerent and fled "screaming into a (nearby) woods." Worried about his safety, Sgt. Boyle and the others pursued him. The "five soldiers repeatedly struggled to try and restrain" Brown as he violently "kicked and bit" them to get away.
An hour later, desperate to get him safely back to base, Sgt. Boyle used a choke hold he learned in the military to subdue Brown. When they got him back to the base, Brown was no longer breathing.
"He was protecting the other soldiers while protecting PFC Brown from himself and he just wanted to get him back to post," his mother said.
She said her son did that night what he was trained by the Army to do.
"To never leave a man behind, whether you're on the battlefield or you're in civilian world. You're a soldier 24, seven. You leave with these buddies. You come back with these buddies," she said.
That's not how the Army saw it. To them, Sgt. Boyle had crossed the line. He was charged with involuntary manslaughter and put on trial. A military jury, in a 6 to 3 decision, convicted Boyle. The Army's autopsy, a key part of the evidence, concluded Brown's death was a homicide caused by asphyxia. But initially the Army Medical Examiner had found both cause and manner of death as undetermined.
"There was no good explanation as to why it was changed from undetermined to homicide," said former New York City Medical Examiner Michael Baden.
The world renown forensic pathologist examined the army's autopsy records and testified in Sgt. Boyle's defense. He says to change the findings with no new forensic evidence is highly unusual and unethical. But even more disturbing to him is how the military examiner missed the significance of Private Brown's abnormally large heart.
"Private Brown had a very enlarged abnormal bad heart. The kind of heart that could set-off a fatal cardiac arrhythmia, be exertion, as he was running around for close to an hour or by emotional upset, which also was occurring while he was intoxicated," Baden said.
As Sgt. Boyle sits in a military prison, his parents fight for his release and blame the Army for a lack of compassion that made a tragic accident much worse.
"It's a betrayal, what the army is doing to my son and the other soldiers," his father, Bob Boyle, said.
The other soldiers avoided prison by taking a plea bargain.
The Army did NOT respond to our repeated phone calls about the case which their prosecutors successfully argued that SGT. Boyle did not have license to choke Private Brown and that he simply went too far.
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