September 11, 2003

By Bob Stevens


Question: How much of what a private investigator discovers can be used in a court of law and what are the guidelines for that? Seems to me that if you want to give someone the blues, just hire a private investigator to watch them for a month. Chances are they'll do something wrong and you can sue them for it.

Curious in New Mexicos?

Dear Curious:

Virtually everything that a private investigator discovers can be used in court, so long as it meets the court’s rules concerning admissibility, such as hearsay rules.

The Fourth Amendment to the U.S. Constitution protects Americans against unreasonable searches and seizures by government officials. The so-called “Exclusionary Rule” holds that evidence obtained by government officials in violation of the Fourth Amendment is ordinarily inadmissible in a criminal trial. The Fifth Amendment of the U.S. Constitution provides protections against self-incrimination. This means that if the police fail to inform a suspect of his or her right to remain silent (commonly called a “Miranda Warning”), and the suspect confesses, the confession cannot be introduced as evidence in the suspect’s trial.

Miranda and the Exclusionary Rule apply to evidence obtained through illegal search and seizure or improper questioning by government agents, such as the police. Private investigators are not government agents; therefore, these rules do not apply to evidence or confessions obtained by private investigators, unless the PI is acting at the request of, or on behalf of a government agent. For instance, the police can’t get around the Exclusionary Rule by asking a PI to conduct a search for them.

In civil cases, most evidence obtained by private investigators is admissible, except in recent years courts have generally excluded evidence obtained by a practice known as “roping.” Private investigators are often called upon to follow individuals suspected of submitting fraudulent insurance claims. They will attempt to observe and film or videotape the claimant engaging in some activity that should be prohibited by his or her alleged injury. This often calls for many, many hours of boring surveillance. Some investigators in days gone by would speed up the process by enticing the subject to engage in some act that should be impossible given the nature of the supposed injury. This was called “roping.” Probably the most common form of roping was to follow the subject to a store or mall, deflate one of the subject’s car tires while he was shopping, then film him changing the tire, despite his bad back. This kind of evidence is no longer acceptable. In fact, many investigators won’t even bother to film a subject changing a legitimately flattened tire because the judge will most likely assume the subject was roped and throw out the evidence.

I know of one investigator who would send claimants a letter telling them they’d won a free fishing trip, and enclosing a pass for a deep-sea fishing boat. He’d then film them casting and reeling in fish all day with their supposed injury that allegedly kept them from being able to work. Another dodge he’d use was to hire the subject to do some work at the P.I.’s mountain cabin for a day or so, such as roofing or painting. He’d film the scofflaw laboring away despite his debilitating injury, then turn the guy into his insurance company for filing a fraudulent claim. He not only made a lot of money catching scammers, he wound up with a really nice cabin. These kind of activities would constitute roping and are no longer permissible.

Even though evidence obtained through some illegal means might be admissible, it is important to understand that a private investigator who commits a crime or tort (civil wrong) in order to secure evidence could be subject to civil or criminal prosecution. The fact that evidence I obtained helped to convict some bad guy won’t give me much comfort when I’m sitting beside him in a jail cell or bankruptcy court because I violated his rights.

As for the second part of your question concerning watching someone and then suing them for something they did wrong, keep in mind that you don’t have the standing to sue someone unless they have injured you. Before you can sue someone you must be able to establish that the person committed an act or omission to act that caused you an injury. If you sue them improperly, the other party may well turn right around and sue you for malicious prosecution or abuse of process.

Rule Number One of The Stevens Agency has always been "I Don't Go To Jail." I'm almost as adamant about not getting sued.


THROUGH A PRIVATE EYE DARKLY is a column dedicated to questions regarding private investigation. Please send questions to and please understand that Bob may not be able to answer each and every question though every effort will be made in that endeavor.

Denise Baton

Copyright © 2001,2002,2003 Robert A. Stevens