Nevin was educated at St. Ignatius College Preparatory, graduating in 1961, and at the City College of San Francisco and the University of San Francisco. He joined the San Francisco Police Department in 1965, serving for 27 years and reaching the rank of Inspector.
He served on the Daly City Planning Commission from 1979 to 1982, when he was elected to the Daly City Council. He was Mayor of Daly City in 1984 and 1989. From 1989 to 1992, he served on the Criminal Justice Council of San Mateo County and the Narcotics Task Force, a subcommittee of the Criminal Justice Council. From 1992, when he retired from the SFPD, to 2004 he served on the San Mateo County Board of Supervisors, advocating the medicinal use of marijuana during his tenure.
He unsuccessfully ran to represent District 8, which encompasses western San Francisco and nearly all of San Mateo County, for the California State Senate, seeking the Democratic nomination in the Primary against Leland Yee. In his political career, Nevin focused on transportation issues, including the expansion of BART and Caltrain, as well as gun control, education, and health care.
After being termed out from the San Mateo County Board of Supervisor, Nevin briefly served under a controversial appointment to the SamTrans board of directors seat reserved for "public" members. Nevin was appointed as Executive Director of the Service League of San Mateo County on August 22, 2006.
Nevin died on Dec. 1, 2012 of esophageal cancer. Nevin was married for more than 35 years to Kathleen, and they produced three children: Mike, Jr., Michelle, and Tim.
- St. Ignatius College Preparatory website. "Michael Nevin '61, former San Mateo County Supervisor, dies at 69". Retrieved December 2, 2012.
- Michelle Durand. "Mike Nevin, former county supervisor, dies". Retrieved December 2, 2012.
- Marion Softky. "SamTrans may alter how it picks members of its board of directors". Retrieved December 2, 2012.