John Zielke

Title & Affiliation
Fellow of Practice Crime and Justice Policy Research Program
Visiting Instructor Sociology and Criminology
Adjunct Instructor Criminology, Law, and Justice


  • Leadership Development Program Graduate, Federal Judicial Center, Administrative Office of the United States Courts, Washington DC
  • MA, Law Enforcement Administration, Western Illinois University
  • BS, Sociology and Law Enforcement Administration, Western Illinois University

John Zielke’s career experience includes 29 years in the area of community based corrections.  After interning with DuPage County Court Services in Wheaton, Illinois, he worked as an adult probation officer and juvenile counselor in Lake County Court Services in Waukegon, Illinois.  After obtaining his Master’s degree, he maintained employment with Rock Island County Court Services in Rock Island, Illinois, before starting his career with the United States Probation Office (Northern District of Iowa) in Cedar Rapids, Iowa.  John was employed with the U.S. Probation Office for over 26 years in the capacities of United States Probation Officer, Senior United States Probation Officer (Drug/Alcohol Treatment Specialist), Supervising United States Probation Officer, Deputy Chief United States Probation Officer, and Chief United States Probation Officer. He was Chief for the last 9 1/2 years of his federal probation career. 

While in graduate school, John conducted his Master’s thesis on the influence of probation officer recommendations on actual sentencing decisions.  While Chief Probation Officer for the Northern District of Iowa, he spearheaded a study on the effectivness of Core Correctional Practices and another study on the detection and deterrent effect of probation officer home contacts.

John’s has taught classes at Kirkwood Community College, Mount Mercy University, and the University of Iowa.

Research Interests

  • Community-based corrections