John P. Houlihan was born in Columbus, Ohio and has resided in DuPage County since 1965. He attended Glen Park Elementary School, Glen Westlake Junior High School, and in 1979 he graduated from Glenbard East High School (Lombard, Illinois). In 1983, he earned his Bachelors of Arts degree in Economics from Grinnell College (Grinnell, Iowa).

Mr. Houlihan attended Drake University Law School in Des Moines, Iowa, where he obtained his Juris Doctor in 1986. He was a junior and senior member of the Drake University Law Review, participated in a Prosecutorial Internship through the Polk County Attorney's office, and participated in Drake University Law School's Clinic representing elderly and indigent clients.

After graduating law school, in 1986 Mr. Houlihan joined the law firm of Mirabella & Kincaid, P.C. In 1991, Mr. Houlihan became a principal in the law firm of Mirabella & Kincaid, P.C., and maintained that position until 2001. In May 2001, along with Joseph M. Beck, Mr. Houlihan formed the law firm of Beck, Houlihan & Scott, P.C. The law firm was later renamed to Beck & Houlihan, P.C. in 2010. Mr. Houlihan's practice is concentrated in the areas of criminal/traffic law, juvenile law, civil practice and litigation, bankruptcy, real estate, and family law. Mr. Houlihan has extensive trial experience, having tried several hundred cases to verdict.

Mr. Houlihan was admitted to the State Bar of Illinois in 1986. He is also admitted to practice in the United States District Court for the Northern District of Illinois as a member of the trial bar. He has been admitted to the Capital Litigation Trial Bar of the State of Illinois to represent criminal defendants in death penalty cases.

Mr. Houlihan is a member of the DuPage County Bar Association, where he has served as Co-Chairman of the Younger Members Committee (1988-1989); Chairman of the Criminal Law Committee (1990-1991); and Chairman of the Membership Committee (2000-2001). He is also a member of the Illinois State Bar Association.

Mr. Houlihan currently serves as an arbitration judge for the DuPage County Arbitration Center and as an arbitrator for the DuPage County Domestic Relations Fee Arbitration Program.
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John P. Houlihan is married and has three children. He has extensive community involvement as a coach of travel softball, basketball, and soccer. Mr. Houlihan has also served as a member of the Wheaton Park District softball/baseball board and on the parish council of St. Daniel the Prophet Church in Wheaton.
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