Welcome to NLIS Investigations!

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NLIS Investigations is a fully licensed and insured detective agency, serving Illinois and Wisconsin, run by the private investigator William Dorsch. William Dorsch is a retired homicide detective from the Chicago Police Department. He has 30 years of law enforcement experience and more than 10 years as a private investigator. He is retained by many well known defense attorneys and by families of unsolved homicide victims. He is an expert at locating and interviewing witnesses and he often testifies in these homicide investigations as an expert witness.
View William Dorsch' Resume | Jump to Services | View Contact Information.

Experienced Criminal Investigator

   The art of investigation lies in gathering and evaluating information and evidence by which any alleged matter of fact is proved or disproved. The skilled investigator must be able to elicit useful information that is admissible in court. He must know how and when to ask the "right" questions.
   My experience has taught how to interview victims, witnesses, complainants and suspects, and to utilize a variety of sources to obtain essential information. I have developed the skills and techniques to recognize, collect, evaluate, process, and preserve evidence.
   After data has been collected, collated, and analyzed, it must be reported. Common sense and sound judgment enhanced by my past experiences have prepared me to assist you in your investigative needs.

“Clients choose attorneys for their excellence in legal work. Attorneys choose me for my excellence in investigation.”


   NLIS Provides the Following Services

  • Review Reports
  • Evidence Interpretation
  • Locate and Interview Witnesses
  • Crime Scene Interpretation
  • Ballistic Evidence
  • Courtroom Strategy
  • Record Retrieval and Research
  • Forensic Evidence
  • Background Checks
  • Criminal Record Checks
  • Surveillance
  • Photography and Video
  • Locate Expert Witnesses
  • Police Procedures & Training
  • Police Shootings & Guide-lines
  • Police Line-ups
  • Jury Selection
  • Expert Witness Testimony