Derek Mosley graduated from Marquette University Law School in 1995. After graduation he served as an Assistant District Attorney for Milwaukee County from 1995-2002. As an Assistant District Attorney, he represented the State of Wisconsin in over 1,000 criminal prosecutions. In 2002, Mr. Mosley was appointed Municipal Court Judge in Milwaukee. At the time of his appointment, he was the youngest African-American to be appointed judge in the State of Wisconsin. For ten years Mr. Mosley served as the Chief Judge of the Milwaukee Municipal Court. In 2023, Mr. Mosley became the Director of the Lubar Center for Public Policy Research and Civic Education at Marquette University Law School.

Judge Mosley sits on the Board of Directors of several organizations including the Greater Milwaukee Foundation, Froedtert Hospital, the Urban Ecology Center, the YMCA of Metropolitan Milwaukee, Safe & Sound, Divine Savior Holy Angels High School, the United Way Diversity Leadership Committee, and Transcenter for Youth. He has been a lecturer at both Marquette University Law School as well as the University of Wisconsin-Milwaukee. He sits on the Supreme Court of Wisconsin’s Judicial Education Committee. He received the Leaders in the Law Award from the Wisconsin Law Journal. He was inducted into the Milwaukee Community Journal’s Academy of Legends, named one of the Philanthropic 5 by the United Way, recipient of the Dean Howard B. Eisenberg Public Service Award from Marquette University Law School, voted “Jurist of the Year” by the Justinian Society of Lawyers, Professional of the Year by ONEMKE & The United Way, named Law Enforcement Official of the Year by Safe & Sound, received the William C. Frye Civic Engagement Award from the Greater Milwaukee Foundation, was named “Milwaukeean of the Year” and “Milwaukee’s Most Trusted Public Official” by the Shepherd Express, was inducted into the Milwaukee Business Journal’s 40 Under 40 Hall of Fame, and received the Robert H. Friebert Social Justice Award from the Milwaukee Jewish Federation. Judge Mosley routinely speaks both nationally and internationally about Unconscious Bias and Black History. Also, as a kidney transplant recipient, he is an ardent supporter of Donate Life Wisconsin, the National Kidney Foundation, and Versiti (formerly the Blood Center of Wisconsin). He currently serves as a Donate Life Hollywood advisor to the television and movie industries to promote accurate depictions of organ donation and transplant on television and in movies. In his spare time, Judge Mosley is a local Milwaukee foodie, and served as a 2022 James Beard Judge for the James Beard Foundation. Judge Mosley was recently honored by the Milwaukee Press Club with the “Headliner of the Year” Award in May.