(WWJ) This week, Warren Deputy Police Commissioner Matthew Nichols -- currently on unpaid leave over allegations of excessive force -- filed suit against the department alleging breach of contract.

He wants the court to order the department to bring him back to work, and award him back pay.

This move comes eight days after Macomb County prosecutors declined to press charges in the case.

The lawsuit also claims the department's internal investigation against him had been completed, though Police Commissioner Bill Dwyer says the case remains open and internal investigators are still determining if criminal charges against Nichols will be filed.

Dwyer said his department will file a motion to dismiss Nichols' suit.

"It's saddening to me that I was named individually in this lawsuit," Dwyer said. "And then the allegations that are alleged in the lawsuit, which are totally untrue."

The actions by Dwyer and the city have caused him embarrassment, humiliation, mental anguish and damage to his reputation, Nichols alleges in his suit, according to the Macomb Daily.

Dwyer told the Macomb Daily the lawsuit is an attempt to force the department to drop its internal investigation -- "which I’m not going to do.”

The allegation against Nichols stem from an incident July 18, 2018 in the parking lot of the Menards’s store on Van Dyke, south of 14 Mile Road. As three suspected shoplifters were taken into custody, one of the suspects reportedly became unruly. Nichols was accused of striking a suspect in the throat with an open hand.

Nichols responded to that allegation in his lawsuit, writing it was self defense. "During the action of placing the defendants under arrest, plaintiff had to protect himself by placing his hands on one of the defendants,” the lawsuit states.

While in custody, the suspect complained of an injury and was taken to an area hospital where doctors treated him before he was returned to lockup.