Pat O’Brien was born and raised in Chicago, where he attended St. Ignatius High School. Upon receiving his B.A. from the University of Notre Dame, Pat returned home to attend DePaul University College of Law. Pat became a licensed attorney in the State of Illinois in 1975 and has practiced continually since, working in both the public and private sector.
Pat has twice worked in the Cook County State’s Attorney Office, handling high-profile cases representing the State of Illinois, and as a result of his dedication to serving justice, Pat was appointed to high-level leadership positions in the Felony Review Unit as Felony Trial Supervisor; Bureau Chief of the Criminal Division; and finally, Chief Deputy, accountable for over 800 Assistant Attorneys handling criminal cases in Cook County.
Pat also served as an Assistant Illinois Attorney General where he assisted State's Attorney's Offices across the State of Illinois with major criminal cases, often working closely with the elected State’s Attorneys in each county.
Pat O’Brien’s impressive record as a public attorney served him well, when in 2006, Pat was elected as a Judge of the Cook County Circuit Court, where he presided in both criminal and civil courtrooms for 8 years, before returning to private practice.
Given Pat’s extensive prosecutorial and judicial experience, Pat O’Brien’s private practice has concentrated on criminal law, where he has provided fair representation for defendants. During this time, Pat has also been honored to be appointed a Hearing Officer for the City of Chicago Liquor Commission and as Attorney for the Police Board.