Eric Ruch was convicted in September of voluntary manslaughter for the 2017 death of Dennis Plowden. A jury found him not guilty of third-degree murder.
Ruch was convicted of 11.5 to 23 months behind bars for the deadly shooting.
District Attorney Larry Krasner called the sentence "concerning" and "troubling" because the standard range is a minimum of 54 months in prison.
"We respectfully request that the Court reconsider its sentence, and sentence the defendant within the state standard guidelines. His conduct warranted such a sentence, and it would be the just result," he said.
The felony manslaughter charge carries a term of up to 20 years in prison.
Ruch was on trial for the shooting death of 25-year-old Plowden following a high-speed chase through Germantown.