After a late-night dip, a group of teenage boys decided to toss their soaked skivvies onto a West Virginia trooper’s parked cruiser. The trooper’s wife rousted her husband awake. He then suited up, assigned himself on-duty, and went out prowling for hours to get some payback.

He found three boys down the street from where his cruiser was parked, and pegged them for the prank. A skirmish ensued with one particular boy he knew; and after the boy allegedly resisted arrest the trooper fired off pepper spray, whacked the boy in the head with his baton, and finally drew his service pistol and squeezed off two deadly rounds.

It’s been a year full since the boy, Timothy “Timmy” Hill, breathed his last. This week the boy’s parents filed a civil lawsuit against that trigger-fingered trooper claiming he used his badge to bully and ultimately bury the unarmed youth.

Timothy Hill was described by those who knew him as “shy” and “nice.” He turned 18 on May 14, 2014.

Hill would only live a month as a legal adult.

Many of the circumstances that led to his short life ending so suddenly remain shrouded in mystery. Timmy had been sleepless on the night of June 13 of last year. He then texted two of his friends to meet him at his home.

The trio of boys went swimming and at some point they separated. Hill’s two friends decided that “it would be funny… to leave their wet underwear on someone’s vehicle as they walked home,” according to the civil lawsuit. Strolling by Trooper B.D. Gillespie’s home at around 11:30 p.m. they ditched their wet drawers on the cruiser before booking it.

Gillespie’s wife apparently witnessed the boys and informed her husband.

He then took it upon himself to put in some overtime and determine who was behind the underwear incident. The lawsuit documents go on to question why the trooper felt the need to “warrant an official response.” The trooper “put his uniform on, made a call into his unit to place himself on duty at approximately 11:51 p.m.” to find the boxer short bandits.

The trooper hopped into his cruiser and drove around “for several hours to no avail,” according to the lawsuit.

By 1:30 a.m., the lawsuit states, Trooper Gillespie “was frustrated by his failure to identify the responsible party for the prank” before he came to the Hill home.

And there were Timmy Hill and his two friends.

The two had history.

According to the lawsuit, Hill had caught Trooper Gillespie’s eye for motoring his four-wheelers up and down Kegley Trestle Road, where they both lived as neighbors. Timmy Hill’s parents say Trooper Gillespie was frequently conducting surveillance on their son by using a radar gun and “watching Timmy with binoculars and recording him with a video camera,” according to the court documents.

Some time before the fatal shooting, the trooper had made allegedly unsanctioned house calls to warn the Hills and keep their teenage troublemaker in line.

The court papers say that Trooper Gillespie threatened Hill’s mother with a $250 summons for “setting their trash out too early for pick-up” and then told her he had the law on his side when it came to Timmy.

The trooper allegedly told her he could take Timmy Hill to jail and “could do what he wanted to those who ‘caught his eye,’ like Timmy,” the papers say.

So on the night of June 13, when the trooper flashed his high beams onto the three teens he zeroed in on Hill, the lawsuit states.

Apparently Hill explained that he hadn’t had a hand in the underwear affair. Then Timmy extinguished his cigarette and all three teens took their hands out of their pockets. The trooper let the other two walk.

And then there were two. “Timmy, an unarmed teenager, who was not involved in the prank nor under arrest, was then left alone” with Trooper Gillespie, according to the court papers. The trooper, who stands six-foot-three and weighs in at 240 pounds began to “interrogate” Hill, with his 5-foot-9, 185-pound physique and his case of nystagmus, a condition causing involuntary eye movement, He also suffered from bipolar disorder.

The trooper’s story has it that he tried cuffing the kid before he flailed and fought him off. Gillespie turned to his pepper spray, the lawsuit says, and “sprayed Timmy in the face at point blank range.” Somehow, Hill was “unaffected.” The trooper then “claims he struck Timmy in the head with his ASP baton,” before grappling with him.

A man named Clark “Casey” Crews had been in town visiting his aunt swooped in to help the trooper stabilize Timmy. “I just bolted out the door and asked the officer if he needed assistance and he said ‘Yes, Get him off of me,’” Crews, 52, told the West Virginia Gazette after the incident. After he pulled Hill off of the trooper he said “we tumbled down the hill into a [drainage] ditch.”

The three of them had rolled down into a culvert and as they came to Gillespie felt the need to turn to lethal force.

Crews recalled that once they tussled into the drainage ditch that “we continued to struggle.” “Gillespie then pulled out his gun, aimed it at an unarmed teenger…and fired his weapon at Timmy, hitting Timmy in the head,” according to the lawsuit.

“Timmy was still struggling,” Crews said. “It happened so fast, I’m just glad I didn’t get shot.”

And then Gillespie fired again, this time striking the boy “in the chest,” according to the court papers. When paramedics arrived they found the boy face down, submerged in water, implying, according to the lawsuit, that Gillespie “did not even check the body to see if Timmy may have been still alive…he left Timmy’s face down underwater…”

But Crews didn’t see the trooper’s actions as anything but heroic. After the bullets felled Timmy, Crews said the trooper “was shaken up.” While he took one life, Crews believes Gillespie saved two lives that night. “His life was being threatened, and since I was helping, I’m sure he thought my life was in danger too.”

The lawsuit also cites forensic evidence, suggesting that an independent evaluation of Timmy’s T-shirt revealed “no nitrites from gunpowder particles.” That could mean that the bullets were fired at far distance; the trooper therefore couldn’t claim his life was in imminent danger.

“The absence of gunpowder residue and stippling on Timmy’s skin is conclusive evidence that the shots were not fired at close range,” notes the lawsuit notes, which accuses authorities of being unwilling to test Gillespie’s uniform for trace evidence.

After the fatal shooting Gillespie went on“Critical Incident” leave before returning to full duty once the county prosecutor declined to file criminal charges.

Soon after the fatal shooting the U.S. Department of Justice’s Civil Rights Division confirmed it was reviewing the case but nothing further has come out publicly since.

A spokesman with the West Virginia State Troopers referred all questions to its counsel, Gary Pullin. Reached by phone Pullin pointed to the fact that a full internal investigation had been conducted to “determine if there was any misconduct on behald of Trooper Gillespie.” That probe cleared Gillespie of any foul play.

But what’s unclear is if Gillespie was given a sobriety test after firing his gun in this incident. “I don’t know the exact answer other than there was a full investigation conducted to determine the cause of the incident,” he said. And what about other incidents where Gillespie allegedly fired his service weapon on mutltiple calls, killing dogs. “I know he has used his weapon before but I’m not aware of the full extent of the discharging of his weapon,” Pullin said.

On how the young boy and his teen pals managed to be part of a formal call for tossing some wet underwear on the hood, Pullin said that it’s easy to play Monday morning quarterback but that the Gillespie family were scared. “The trooper responded and it was a response to what he considered a threat.”

But ask Michelle Hill and she is left to go on with life without her Timmy. “He was my only son,” she said. “But he was a really good one.”