Loudoun Valley on Friday afternoon fired football coach Danny McGrath. The school provided no reason for the move, continues to pay his coaching stipend and is allowing him to continue to teach at the school, his lawyer said.

On the advice of his attorney, William B. Reichhardt, McGrath declined to comment. Loudoun schools spokesman Wayde Byard confirmed that McGrath had been dismissed as coach, but not as a physical education teacher, and that state privacy laws prohibited him from discussing the reason why.

Angry parents of Loudoun Valley players said the move was retaliation for McGrath’s advocacy for safety for his players. “It was the standard witch hunt,” said Dee Howard, a member of the school’s football booster club. “I think he was fired because he spoke up for the athletes and for their safety.”

McGrath had actively pushed within the county’s athletic system last year for “safety scheduling,” arguing that his school, one of the smallest in Loudoun County, should not play much larger schools with more players. Loudoun officials felt the size difference between schools was not that great, that Valley didn’t play the largest schools in the county, and noted that Valley then won eight of its 10 regular season games.

When Valley competed in the postseason against schools in Division 3 — most Loudoun schools are classified as Division 4 or 5 — McGrath’s team rattled off three more wins before losing in the state semifinals.

Danny McGrath, pictured during his first season as Loudoun Valley’s head football coach, was fired by the school Friday — one week before the Vikings’ regular season opener. (Tracy A. Woodward/The Washington Post)

Shortly before the 2013 season, a Bethesda company named Brain Sentry offered to outfit the entire Valley team with impact sensors, to monitor when a particularly hard hit had been absorbed by a player’s helmet. McGrath and his coaches were directed to draw up protocols for the sensors, but the county did not approve their use before the season ended in December.

Brain Sentry and Inova Neuroscience Research then offered a joint proposal last spring to provide sensors to all of the football and lacrosse teams in Loudoun. County officials felt the devices were not sufficiently tested yet, might impact the safety certification of the helmets, and might cause players to be targeted by other teams. They declined the offer.

McGrath did not speak out on the sensors. But the parent booster club decided to buy a box of the sensors and apply them to the helmets themselves, which they did before the first contact practice earlier this month. An assistant principal stopped the practice and ordered anyone with sensors to sit out. McGrath then told the whole team to take their helmets off.

But the parents said they didn’t want to put McGrath in the middle of the dispute, and they removed the sensors within minutes.

McGrath was called in about 3:30 p.m. by Principal Susan Ross and handed a letter terminating him immediately as football coach, Reichhardt said. The letter said the coach would receive the full amount of his coaching stipend, about $5,200, and the letter would not be placed in his personnel file, Reichhardt said. The team’s season starts Friday with a home game against James Wood.

McGrath, 31, had been the head coach since 2008. He was a starting offensive lineman at Virginia Tech under Frank Beamer and was an All-Met lineman at Herndon High. After going 1-9 in McGrath’s first season, the Vikings were a combined 32-25 over the next five years.

Reichhardt said high school coaches are not entitled to the same due process as teachers, and can be fired almost at-will. But he said he had been representing McGrath since last year because “he was experiencing difficulties” with school administrators, which he declined to specify. “He was scared of losing his job,” Reichhardt said.