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Uncovering Truths, Protecting Interests

Investigations That Deliver Answers

Arch Private Investigations provides full-service investigative support for individuals, attorneys, insurance carriers, and businesses across Missouri. From surveillance and background checks to domestic cases, fraud investigations, and skip tracing, our work is built on 25 years of field experience, proper licensing, and a commitment to doing things right. Every case gets direct communication, thorough documentation, and findings you can act on. Whatever the situation, we're ready to work it.
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Key Services

Insurance Investigations

We work with carriers, adjusters, and SIU teams to investigate claims thoroughly, delivering evidence packages built to hold up under legal scrutiny.

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Surveillance

Whether it's a personal or business matter, our surveillance captures clear, documented evidence you can take to court or act on with confidence.

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Skip Tracing & Locating

When someone disappears from the picture, we find them. Debtors, witnesses, missing persons. Advanced tools, experienced investigators, real results.

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From Consultation To Case Closed

Every case starts with a free, confidential consultation where we define your objectives and outline what the investigation will involve. From there, we build a focused plan and get to work. Surveillance, research, interviews, and evidence collection are all handled personally and within full compliance with Missouri law. You get regular updates throughout, and when the work is done, we deliver a detailed, court-ready report with supporting documentation and media so you can move forward with facts, not guesses.

Michael K. Adelstein | Founder & Lead Investigator

Licensed Private Investigator | MA Criminology | BA Criminal Justice | 25+ Years Investigative Experience

Michael K. Adelstein is the founder and lead investigator of Arch Private Investigations, LLC in St. Louis, Missouri. With more than 25 years of experience across private investigations, loss prevention, and law enforcement, he leads every case personally and delivers the thorough, legally compliant results that individuals, attorneys, insurers, and businesses across Missouri rely on.

25 Years Behind The Facts

This firm didn't start yesterday. Arch Private Investigations is led by a licensed investigator with more than two decades of experience across law enforcement, loss prevention, and private investigations, backed by advanced degrees in Criminal Justice and Criminology. When you hire us, you're working directly with someone who has built a career on getting it right.
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