SACRAMENTO — Federal prosecutors are calling for San Ramon divorce attorney Mary Nolan to serve nearly three years in prison for tax violations and her role in the Contra Costa County “dirty DUI” scandal.”

Nolan pleaded guilty in September to four counts of tax evasion and one count of wiretapping. Authorities say Nolan conspired with Concord private investigator Christopher Butler in 2007 to eavesdrop on the conversations of a client’s spouse via a planted listening device.