Joseph Mensah resigning from Waukesha County Sheriff's Department

Joseph Mensah submits resignation

Joseph Mensah, the Waukesha County sheriff's detective and former Wauwatosa police officer, is leaving the "law enforcement profession."

WAUKESHA, Wis. - Joseph Mensah, the Waukesha County sheriff's detective and former Wauwatosa police officer at the center of an ongoing civil lawsuit, is leaving the "law enforcement profession."

Mensah resigns

What they're saying:

FOX6 News obtained Mensah's resignation letter, which is dated July 17, on Friday.

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"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 the law enforcement profession," Mensah wrote in the letter. 

Waukesha County Sheriff's Department

In thanking Sheriff Eric Severson and others, Mensah wrote in part: "The Waukesha County Sheriff's Department accepted me and brought me into your family when I needed you the most. I am beyond thankful, that I had the opportunity to serve along side (sic) the men and women of this agency."

Mensah's resignation is to take effect on July 31. The sheriff's department acknowledged the resignation and, in a statement, said: "We support Detective Mensah and wish him the best."

Wauwatosa shootings

The backstory:

Mensah shot and killed three people over the course of five years as an officer with the Wauwatosa Police Department: Antonio Gonzales (2015), Jay Anderson Jr. (2016) and Alvin Cole (2020). In each case, the Milwaukee County District Attorney's Office declined to filed charges against him.

Mensah resigned from the Wauwatosa Police Department in 2020 and later joined the Waukesha County Sheriff's Department.

(L-R): Alvin Cole, Jay Anderson Jr., Antonio Gonzales

Dig deeper:

The families of all three people filed civil lawsuits in federal court against Mensah and the police department, alleging the officer used excessive force and the department prompted racism. Those lawsuits were consolidated in September 2022.

U.S. District Judge Lynn Adelman dismissed the Gonzales and Anderson families' claims. He allowed the Cole case to continue.

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In March, a federal case ended with a mistrial after jurors failed to reach a decision on whether Mensah used excessive force when he fatally shot Cole outside Mayfair Mall.

A retrial was scheduled for September.