The Pennsylvania man who fatally shot recent high school graduate in a road rage incident last year will spend the next 20 to 40 years behind bars, a judge decided Thursday.

David Desper, 29, of Delaware County was formally sentenced in the death of 18-year-old Bianca Roberson, who he shot in the head as the two jockeyed for space while merging onto a highway in Chester County. Desper pleaded guilty to third-degree murder earlier this year.

According to CBS Philadelphia, the “emotional” sentencing went on for several hours as Roberson’s family, prosecutors and the judge wiped away tears. Even Desper’s defense attorney was in tears as her client was sentenced.

“I just want to thank them all for doing the right thing by finding justice for my daughter,” said Michelle Roberson, Bianca’s mother.

“It’s my daughter that’s lying there dead,” added Bianca’s father, Rodney Roberson. “So it’s her father and mother that have to carry on for her — the strength. And, I want to believe that I’m my daughter’s strength.”

The tragedy unfolded back on June 28, 2017 when Desper pulled a loaded gun from the center console of his red pick-up truck while fighting with Roberson over a lane entering Route 202 in West Goshen Township, FOX 29 reported. Roberson, who’d just graduated from Bayard Rustin High School, was headed home from a shopping trip with her mother and grandmother at Walmart for college supplies.

She never made it, however.

The teenager’s green Chevy Malibu reportedly swerved into Desper’s truck during the road ruckus, after which Desper fired a single shot into the side of her head. The gunman fled the scene and turned himself into police four days later.

“Why did you pull that trigger and kill my daughter?,” Rodney Roberson asked Desper, noting that his daughter had a promising future ahead of her and was headed to college on a full scholarship. “Was it because she was young? Because she was black? Because she was a woman? Because you wanted to go first in a lane?”

Desper cried as he apologized for his actions, insisting he was “afraid” as their cars dueled for space on the highway.

Judge Ann Marie Wheatcraft acknowledged his remorse but said she didn’t buy that he was scared in that moment.

“I listened to everything that was presented here,” Wheatcraft said, wiping away tears. “Mr. Desper, I believe you’re sorry. I believe you would take it all back if you could. [But] I don’t believe you were afraid. If you are afraid when driving, you hit the break.”

Desper’s attorney sought leniency in the case, considering he’d turned himself into police, but Roberson’s family asked for the maximum sentence.

Even Desper’s mother, who sat despondently in the courtroom Thursday, had the slain young woman on her mind.

“Just please, everyone, just pray for her family,” Wendy Desper cried. “That’s all I ask.”

Both families left the courtroom satisfied with the judge’s decision.

Watch more in the clip below.