Students comfort one another at the site of the crash in Olney, Md., that killed Shawn Gangloff, 15, on Labor Day weekend in 2014. Another passenger, Max Dechter, 17 at the time, was seriously injured. (Michael S. Williamson/The Washington Post)

The 17-year-old driver in a Labor Day weekend crash that led to the death of one Sherwood High School student and left another severely injured pleaded guilty Friday at a court hearing where prosecutors estimated that he was driving 119 miles an hour.

Austin Donovan Hall was impaired by alcohol after an underage party in Olney, Md., in 2014 when he lost control of the car on a curve in the road in a 35-mile-an-hour zone, prosecutors said. The Chrysler convertible he was driving veered and struck a tree.

Shawn Gangloff, 15, was ejected from the car and suffered fatal injuries; Max Dechter, then 17, was severely injured.

At the hearing in Montgomery County Circuit Court, Hall answered a judge’s questions solemnly as he pleaded guilty to a charge of vehicular manslaughter in Gangloff’s death and a charge of causing a life-threatening injury while driving impaired by alcohol. The second charge came in relation to Dechter’s injuries. Hall faces a maximum of 12 years in prison for the two charges.

Prosecutors said Hall’s blood-alcohol level was 0.11 when he was tested about 4 a.m. The crash occurred shortly before 1:30 a.m. Aug. 30.

As part of the plea agreement, Hall’s attorney withdrew a motion for the case to be moved to juvenile court. Hall was indicted on six charges in March, including for allegedly violating restrictions on a provisional driver’s license.

Hall and his parents did not comment after the hearing, but the family’s attorney, Craig Schoenfeld, said they “chose to proceed in this way today because Austin wanted to honor and respect the families by taking responsibility for his actions.”

The Gangloff and Dechter families attended the hearing, with some relatives wiping away tears as the crash was recounted. Max Dechter, still recovering, attended wearing a neck brace and bandages covering one arm.

In an interview after the proceeding, Dechter and his mother said the teenager was hospitalized for five weeks and was in a rehabilitation hospital for five more months. His neck was fractured and an elbow shattered, and he suffered a traumatic brain injury that required him to have to learn to eat and walk again.

“I had to relearn everything,” Dechter said.

“It’s a parent’s worst nightmare: a knock at the door at 1:30 a.m.,” Jackie Dechter said, remembering that she was at first told her son’s chances of survival were poor. “We thought we were going to the hospital basically to say goodbye.”

The Dechter and Gangloff families said they were not looking for the maximum punishment for Hall but believed it was important that the teen take responsibility for his actions. Hall’s sentencing is scheduled for Sept. 10.

“We want a message sent to the community that you have to be accountable for your actions,” said Allison Gangloff, Shawn’s mother. “Anybody who drinks and drives.”

Shawn’s father, Rick, struck a similar note, saying it is important that “there be some sort of sentence that would not only rehabilitate Austin but would send a message to our community that there are consequences for your actions. Our hope is that no other family would have to go through what we have gone through.”

The Gangloffs said they were anguished to hear of the June crash that killed two teenagers recently graduated from Montgomery County’s Wootton High School. That crash also followed a teen party, with authorities citing alcohol and speeding as contributing factors.

“It was just devastating to me,” Allison Gangloff said. “I felt for those families so much.”

“How many county high schools have to go through the same pain?” asked Deborah Potter, the Gangloffs’ attorney.

Montgomery County police spokeswoman Lucille Baur said Friday that Maryland has “social host laws” that allow authorities to prosecute parents or homeowners responsible for venues where underage drinking parties are held, even if they are not present during such events.

In the Olney case, Baur said, the parents were not charged because they were out of the country at the time of the party, and investigators determined that they could not be held accountable in that particular case.

Both families said the months since the crash had been unimaginably difficult. It came after the first week of the school year. Max Dechter said he and Shawn Gangloff were close friends and lacrosse teammates.

“The only reason he’s here is because he was belted,” Jackie Dechter said of her son. “That’s what saved his life.” Shawn was not wearing a seat belt.

Max Dechter said his message to other teenagers would be not to get in a car with a driver who has been drinking. “It puts others at danger and yourself at danger,” he said.