Sheskey, who is white, will not be disciplined for his use of force and is now back on the job after returning from administrative leave on March 31, Chief Daniel Miskinis announced Tuesday.
"Although this incident has been reviewed at multiple levels, I know that some will not be pleased with the outcome," Miskinis said in a statement. "However, given the facts, the only lawful and appropriate decision was made."
In addition to an internal investigation, the Aug. 23 incident was investigated by an outside agency, an independent expert and the Kenosha County District Attorney, Miskinis said. No charges have been filed in connection with the shooting.
The shooting occurred after officers responded to a report of a domestic dispute and were attempting to detain Blake, who had a warrant out for his arrest. After Blake walked to the front of his vehicle toward the driver's side door, Sheskey fired his gun seven times toward his back.
Blake was struck by six of the bullets and is now paralyzed from the waist down.
An unfolded knife was found on the driver's side floorboard of Blake's vehicle, authorities said.
The viral video of the incident captured on a witness' cellphone sparked days of large-scale protests in Kenosha.
Last month, Blake filed a federal civil rights lawsuit against Sheskey, accusing the officer of using "excessive and unnecessary" force.
"We believe that this lawsuit will help establish accountability," B'Ivory LaMarr, one of Blake's attorneys, told ABC News at the time.
In announcing that no officers will be charged in the shooting, Kenosha County District Attorney Mike Graveley said earlier this year that Sheskey was justified in his use of force and was acting in self-defense because Blake was armed with a knife.