Germantown Teen Facing Manslaughter Charge After Deadly Crash

GERMANTOWN, MD — A Germantown man is facing charges for his role in a May 2025 crash that claimed the life of an 88-year-old woman.

Liam Donnelly Coskun, 18, turned himself in to authorities on Nov. 21, Montgomery County police said in a news release. He is charged with negligent manslaughter by vehicle and negligent homicide by vehicle while under the influence in connection with the crash.

The crash occurred shortly after 8:30 a.m. on May 31 at the intersection of Sam Eig Highway and Fields Road in Gaithersburg.

According to police, a blue 2017 Toyota Corolla was stopped at a red traffic signal when it was hit from behind by a blue 2018 Jeep Compass driven by Coskun. The impact caused serious injuries to Gottlieb, a front-seat passenger in the Toyota. She and the driver of the Toyota were taken to an area hospital, where Gottlieb later died from her injuries.

Police said Coskun was intoxicated and traveling at a high rate of speed when he crashed into the rear of the Toyota. Coskun, who was not injured in the collision, was arrested at the scene on suspicion of driving under the influence.

Approximately two hours after the crash, police said Coskun submitted to a breathalyzer test that registered a 0.09 BAC. Investigators also confirmed that Coskun does not have a valid driver’s license in any state, police said.

After completing their investigation, police said investigators determined Coskun was at fault in the crash.

Coskun is currently being held without bond at the Montgomery County Central Processing Unit