John A. DeMarr, P.I. - Investigation Services


The Private Detective and Private Investigations Firm

Since 1988, John A. Demarr, P.I., has been providing professional, licensed private investigation and private detective services, to businesses and individuals in and beyond. Our clients include law firms, insurance companies, major corporations and small businesses.

Our -based private investigations, and our private detectives, also provide many services to private individuals. Our work for individuals includes confidential marital infidelity cases, child custody cases and nanny surveillance.

Our staff includes police-trained, seasoned professional investigators, document experts, interview experts, and industry experts in the credit, collections, lending, and legal fields.

We investigate online and offline. If you have a hunch, we can check it out and find the truth - as we have done for so many clients.

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What a Licensed Private Investigator Knows That Other People Don’t Know

John A. DeMarr Private Investigators Toll free 877-493-3463 is a prominent Los Angeles area PI with extensive experience in difficult and complicated private investigations. Winning a lawsuit, or convincing a judge that your position should prevail on a legal decision, all depends on what evidence you can present to the judge to allow him or…

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Los Angeles Private Investigator Finds He Is Not Hurt!

Some people see their insurance policy as an opportunity to make some quick cash. They file illegitimate claims in order to profit from an event that may or may not have happened. Private Investigators can gather valuable ammunition against a person to uncover fraudulent claims – this is why most insurance companies avail the services…

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