The 18-year-old was handcuffed and detained because officers thought he was carjacking his white grandmother.
The two of them, plus the grandmother’s friend who was also in the car, filed the lawsuit.
In a statement, the department says two people had flagged down officers to point out a carjacking happening nearby.
On squad car dash camera video, the woman can be heard confirming the man in the backseat is her grandson.
The man was held in the back of a squad car for about six minutes.
“I’m guessing what this sounds like is a big misunderstanding,” one of the officers says to him.
Police say the man was detained based on reasonable suspicion.
The lawsuit says it wasn’t reasonable, and that there’s never been proof the officers were flagged down about any carjacking.
The plaintiffs are claiming damages including “severe emotional pain, distress and the loss of enjoyment of life,” among others.
They believe it was a “racially-motivated vehicle stop,” and the man “re-lives that terror every day.”
A witness, Dominique Elliott, recorded cell phone video of the incident.
“They shouldn’t have went that far,” he said. “If you would have seen how surrounded this boy was, and I was just thinking oh my God, I hope they don’t kill him.”
The lawsuit says the Wauwatosa police chief has refused to do a formal investigation of the incident.
To read the department’s full statement on what happened, click here.