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Joseph Mensah investigation


3 Tosa police officers granted immunity during new Joseph Mensah investigation

MILWAUKEE — Three Wauwatosa police officers were granted immunity amid a new investigation into former Tosa officer Joseph Mensah's shooting death of Jay Anderson Jr. in 2016.

Milwaukee County court records show Officer Ralph Sayers, Officer Stephen Mills and Captain Gary Gabrish were granted immunity from any criminal prosecution.

The officers were set to meet with prosecutors leading the new investigation into the shooting death this week. A Milwaukee County judge previously ruled there was probable cause to charge Mensah, who now works as a detective with the Waukesha County Sheriff's Department.

Jay Anderson's parents issued the following statement:

"We hope that because they asked for Immunity they are willing to bring out evidence that should have been told in 2016. regarding our son. We believe that a lot of people were covering up for Joseph Mensah. As Wauwatosa police officers the fact they are asking for immunity is troubling. It is also very troubling that Mensah is a presently a detective with the Waukesha Sheriffs Dept. Whatever Officers Ralph Salyvers, Stephen Mills, and Gary Gabrish are willing to say now should have been said in 2016 after our son was killed. If they were covering up evidence they should also be held accountable.

The evidence is clear that Mensah should have been criminally charged for killing Baby Jay in 2016. If he were charged then, Alvin Cole would likely be here today."

Last year, Milwaukee County Circuit Judge Glenn Yamahiro authorized Milwaukee attorney Scott Hansen and La Crosse County District Attorney Tim Gruenke to serve as special prosecutors in former Wauwatosa officer Joseph Mensah's case.

Mensah shot and killed Jay Anderson Jr. after discovering him sleeping in a park after hours in 2016. Anderson was one of three people Mensah killed during a five-year stint on the Wauwatosa police force.

Prosecutors opted not to charge him in any of the deaths, but Yamahiro decided to reopen Anderson's case this summer.

“We have a lot of investigating to do,” said Hansen as he left the Milwaukee County Courthouse Wednesday. “We intend to do a very thorough, independent job.”

Hansen and Gruenke will go through all the evidence. They could ask police for more reports and issue subpoenas. They have 60 days to make a final charging decision, a period that ends in early February.

Attorney Kimberley Motley, who represents the Anderson family, previously said these special prosecutors are very experienced and already well-established.

“I have yet to learn more about them, I don’t know them, but I do think it's good the judge didn't pick someone who wants to make a name for themselves with this case,” Motley said.

Hansen has been with Milwaukee law firm Reinhart, Boerner, VanDeuren for nearly 50 years.

Gruenke has been a prosecutor for 25 years and has served as the La Crosse County DA for the past 13.

Hansen and Gruenke will only be reviewing the shooting death of Jay Anderson. Mensah was patrolling Madison Park in 2016, when he found Anderson sleeping in his car. Mensah says Anderson reached for a gun as he walked up to the car. Anderson was shot several times.

Mensah was involved in two other fatal shootings, over five years as a Wauwatosa Police Officer. In 2015, he shot and killed Antonio Gonzalez, 29. In 2020, Mensah shot and killed Alvin C, 17, outside Mayfair Mall.

All of Mensah's shootings were ruled justified by the Milwaukee County District Attorney.

Mensah resigned from the Wauwatosa Police Department in 2020 after collecting a severance payment. He is now working for the Waukesha County Sheriff's Department.

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