Killer of DoorDash driver in Ferndale sentenced to decades in prison

Police found Diallo outside his vehicle with a gunshot wound. He was later pronounced dead.

By: Mike Koury | Woodward Talk | Published February 6, 2026

Simms

At 26 years old, Mamadou Diallo was gunned down last year by Terrell Simms during an altercation in Ferndale. Diallo, a Senegalese immigrant, was described by friends as a “respectful” man who loved soccer.

File photo provided by the Ferndale Police Department

FERNDALE — A man found guilty of the murder of a DoorDash driver last year in Ferndale presumably will spend the rest of his life behind bars.

Terrell Simms, 39, was sentenced on Jan. 27 to a minimum of 37 1/2 years and maximum of 80 years in prison for the killing of Mamadou Diallo last year after being found guilty of second-degree murder. According to the Michigan Department of Corrections, Simms’ earliest release date will be Oct. 7, 2064.

He also was found guilty of carrying a concealed weapon, being a felon in possession of a firearm and possessing a firearm during the commission of a felony.

"Mamadou Diallo was trying to earn a living and provide for his family on the night he was murdered by Terrell Simms,” Oakland County Prosecutor Karen D. McDonald said in a prepared statement. “While nothing can bring Mr. Diallo back, this sentence is significant and holds his killer accountable."

Diallo was killed at approximately 1:45 a.m. March 9 last year. He was working as a DoorDash delivery driver, having just made a pickup at a Ferndale White Castle on Woodward Avenue. He attempted to merge onto southbound Woodward when a GMC truck nearly collided with his vehicle.

The truck, driven by Simms, slowed down and waited for Diallo in his vehicle to catch up to him on the road. It was here at Eight Mile Road that Simms fired six gunshots at Diallo, according to investigators.

Ferndale police arrived at the area sometime after, where Diallo was found lying on the ground outside his vehicle. He was pronounced dead after being taken to a hospital.

After a monthlong investigation, authorities were able to arrest Simms on April 9 for Diallo’s murder. The case advanced to the Oakland County Circuit Court, where Simms was found guilty on Oct. 23.

In addition to his time in prison, Simms also was ordered to pay restitution in the amount of $7,519.

Simms’ attorney, Adam Clements, could not be reached for comment at press time.