A former Wauwatosa police officer who killed three people in the line of duty before joining the Waukesha County Sheriff’s Department is leaving law enforcement.
According to a resignation letter dated July 17, officer Joseph Mensah will step down from the department at the end of the month.
“After much consideration, I feel it would be in the best interest of the Sheriff’s Department, the community, my family and my own personal well-being that I transition out of law enforcement,” Mensah wrote in the letter addressed to Waukesha Sheriff Eric Severson.
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Mensah joined the Waukesha County Sheriff’s Department in January 2021, months after resigning from the Wauwatosa Police Department. He had been on suspension in Wauwatosa following his third fatal shooting in five years.
The officer was cleared by former Milwaukee County District Attorney John Chisholm in all three on-duty shootings. The last shooting, which left 17-year-old Alvin Cole dead, caused a week of protests after Chisholm announced no charges would be filed against Mensah.
A civil trial for a lawsuit against Mensah filed by Cole’s parents ended in a hung jury in March, according to reporting by the Milwaukee Journal-Sentinel.
“The Waukesha County Sheriff’s Department accepted me and brought me into its family when I needed them the most, and I am beyond grateful and thankful that I had the opportunity to serve alongside the men and women of this agency,” wrote Mensah, who was a detective with the department.
Nicholas Wenzel, a lieutenant with the sheriff’s office, said the office acknowledges his resignation.
“We support Detective Mensah and wish him the best,” Wenzel wrote in an email.
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