Several years ago, I wrote the column “P.I. Confidential” for the organization Novelists, Inc.  As the organization’s membership were published full-length commercial novelists, I geared the information to writers.  At the end of the article I answer a writer’s question about her fictional PI interviewing an intoxicated suspect who confesses, out of the blue, to a crime…unfortunately, her fictional PI did not have any recording equipment with her.  An interesting scenario for fiction, and one a real-life PI would try to never find him/herself in!

The Art of Interviewing: The Pitfalls, Pratfalls, and Shortfalls

by Colleen Collins, all rights reserved

Private investigators often conduct interviews, typically on behalf of attorneys for cases being litigated. To conduct successful interviews, a P.I. must have good people and communication skills, eye and magnifying glassand know how to elicit the desired information without falling prey to errors of ethics and omissions, equipment malfunctions, and simple human error, which we’ll call pitfalls, pratfalls, and shortfalls for this article. Although these failings can undermine a real-life P.I.’s investigation, they’re great in fiction because they can add depth to a character, introduce a plot twist, or notch up the tension.


Pitfalls are unsuspected traps in an interview that typically surface after its conclusion. For example, an investigator completes an interview with a friendly witness who identifies a criminal. But the P.I.’s success is short-lived when she later learns this witness changed his story, and now claims the investigator misrepresented what was said, or accuses the investigator of being threatening or intimidating. Why would a seemingly friendly witness do this? A few possibilities are to cover his involvement in a crime, to protect the accused or the real perpetrator, or to get out of being subpoenaed to court. Regarding the latter, witnesses who have failed to show up in the past for their own court obligations might be concerned that testifying at others’ trials means they will be taken into custody on the spot for their own problems. And they’re right.

Unfortunately, the law will step in if there’s reason to believe that an investigator caused an average, reasonable person to become fearful, in which case the investigator can be charged with intimidating a witness. Not a good scenario for a real-life P.I., but great fodder for a fictional one.

Here’s a few tips for how an investigator might protect herself from such pitfalls:

  • Choosing a public place, such as a restaurant, for an interview.  People tend to be on their better behaviors when others are around.
  • Documenting the interview–for example, having an associate join the interview or film/record it from nearby. By the way, this filming/recording needs to be conducted in a public place (a coffee shop, a public parking lot) to avoid charges of eavesdropping.
  • Researching the witness ahead of the interview. Knowing a witness’s soft spots helps a P.I. avoid allegations of threats, manipulation, or intimidation.


These are the dumb mistakes investigators sometimes make in real life, which can add humor, conflict or tension in a story. For example, a P.I. rushes out to an interview and forgets to put fresh batteries into a digital recorder. Later, just as the P.I. has persuaded the witness to open up…the device dies. Or a P.I. tapes an interview in a noisy bar. Later, he realizes the bar background noises have blocked critical portions of the recording. For the malfunctioning recorder, an investigator might start taking notes. For the blocked recording, an investigator might piece together from cell phonememory portions of the interview, or better yet, pay a digital forensics expert to remove the background frequencies.

A more serious pratfall is not checking ahead of time if a witness or party to the case is represented by an attorney. If an investigator interviews a represented individual, the judge presiding over the case is likely to exclude the interview from evidence. Also, the investigator and the attorney she works for could be disciplined by their respective licensing authorities.


In a courtroom, a lawyer should never ask a question he doesn’t know the answer to.  The opposite is true for a P.I.–outside the courtroom, witnesses may hint at an important fact, or inadvertently let something slip. A sharp investigator catches that, and follows up with questions on that thread.

Answering a Writer’s Question About Interviewing a Suspect

Writer’s Question: In my story, I have a scene where the P.I. is interviewing an intoxicated witness, who out of the blue confesses to being the murderer. Unfortunately, the P.I. has no recording equipment. Later, she returns to re-interview him, but he’s disappeared. What can my P.I. do?

Colleen’s Answer: Your P.I. can still testify about the witness’s confession, or admission, in front of a jury at the charged defendant’s trial. However, this third-party admission as relayed by the P.I., without corroborating evidence, will most likely not convince a jury.

Happy writing, Colleen

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