Mary Seminara-Schostok was born on December 8, 1958, in New Castle, Pennsylvania. She served as an assistant public defender in Allegheny County, Pennsylvania, then practiced privately in Pittsburgh. After moving to Illinois, she served as an Assistant State's Attorney in the Lake County State's Attorney Office. Judge Schostok's service on the bench commenced in May 1998 when she was appointed to serve as an Associate Judge in the 19th Judicial Circuit. She was appointed as a Circuit Judge in 2001 and was elected in 2002. During her 10-year tenure as a Circuit Judge, Judge Seminara-Schostok presided over both criminal and civil matters, and supervised the Juvenile Division, the Misdemeanor and Traffic Divisions, and the Law Division. She was appointed an Appellate Judge in the Second District Appellate Court in August, 2008. She is currently the Third Vice-President of the Illinois Judges Association, and has been active with several civic and legal organizations including the D.A.R.E. program; the Lake County Haven, a homeless women's shelter; Big Brothers/Big Sisters of Lake County; the Red Ribbon Week at the Lake County Courthouse; and the American Bar Association judicial internship program. She serves as Chair of the Criminal Law and Probation Committee of the Illinois Supreme Court. She and her husband Michael have three children.