Professional Affiliations


Insurance Investigation

Private Investigation

If you are serious about your results, we are your finest choice.


Undercover Operations 
True Espionage

Disguising one's own identity, or assuming a pseudo-identity (for the purpose of gaining trust from an individual—or a targeted organization—in order to learn, or confirm, confidential information and/or to secure evidence) is the heart & soul of true investigation. And it is not for the faint-hearted or inexperienced.From simple pretext work on a phone call, to a full-blown personal identity assumption that can last for months, this type of core investigation requires both professional acumen as well as inherent street smarts to pull off.

J. Koerner Investigations is founded by an individual who possesses both key elements. This type of work requires a natural, who can think on his feet, is comfortable in a wide-variety of real-life challenges, as opposed to individuals who sit behind a desk all day and make phone calls from the safety of a controlled, sterile environment. True undercover work is the riskiest type of PI work, and it is the most involved, so a minimum of a $10,000 retainer fee is typically required, upfront, before the project will begin.

J. Koerner Investigations
P.O. Box 4186
San Dimas, CA 91773
Tel: (909) 225-5448
Fax: (909) 267-9760