Do Polygraph Tests Hold Up in Michigan Courts?
Everything You Need to Know About the Legal Value of a Lie Detector Test
Polygraph tests, often known as "lie detector tests," are a powerful tool in investigations—but do they actually carry weight in court? At Westbrook Investigations & Consulting, we’re often asked by clients whether a polygraph result will stand up legally, especially in Michigan. The answer depends on the context, how the test was conducted, and who is interpreting the results.
✅ What Is a Polygraph Test?
A polygraph measures physiological responses—such as heart rate, blood pressure, and respiration—while a person answers a series of questions. The assumption is that deceptive answers cause measurable stress reactions.
At Westbrook, our examiners use validated, court-recognized formats and are certified in the most up-to-date protocols. We perform both criminal and civil examinations, as well as pre-employment screenings.
⚖️ Are Polygraph Tests Admissible in Michigan Courts?
In Michigan, polygraph results are generally not admissible in criminal trials, unless both parties (prosecution and defense) agree to allow them. That said, polygraph exams are still widely used in pre-trial strategy, investigations, and plea negotiations.
In civil matters or administrative proceedings (such as employment disputes), polygraphs may hold more weight. They are often used to:
Support internal investigations
Validate witness credibility
Resolve employee misconduct claims
Strengthen a pre-litigation posture
🕵️ Why Polygraphs Still Matter
Even when not admissible, polygraphs play a crucial behind-the-scenes role:
They guide investigators toward more effective questioning.
They may support or challenge a suspect’s narrative.
In many cases, they lead to confessions or clarifying admissions.
At Westbrook Investigations, we’ve helped attorneys and private clients use polygraphs strategically—not just as a truth-finding tool, but as a catalyst for next steps.
🛡️ Our Polygraph Approach
Westbrook offers polygraph examinations for:
Attorneys preparing criminal or civil cases
Businesses conducting high-stakes internal reviews
Private individuals navigating sensitive family or relationship issues
We maintain strict professionalism, confidentiality, and impartiality. Each session includes:
A comprehensive pre-test interview
Scientifically validated testing protocol
Clear, defensible written reports
Availability for expert testimony when applicable
📍 Serving All of Michigan
While based in Metro Detroit, Westbrook proudly serves clients across the entire state of Michigan. Whether you’re in Grand Rapids, Lansing, Flint, or Ann Arbor, we bring professional-grade testing wherever it's needed.
