How NOT to Conduct an Investigation Interview

Lessons learned from a failed interrogation

Posted by Guy Parent in on May 16th, 2012

Telling a “pompous know-it- all” private investigator in his 15th year of dedicated practice (this would be me) that he was required to extract a confession of guilt from a guilty subject was nothing short of a challenge on the level of a double-dog dare.

A hospital’s Administrative Director called, introducing me to his Director of Security (we will call ‘John’). They were both befuddled when cash shortages began to appear through missing funds from the parking lot’s coin-operated vehicle gate and suspected internal fraud.

John was quick to share some of his personal reservations regarding the honesty and integrity of a few of his newly hired security personnel. He supported his suspicion, citing the collection process that only required security to empty the money box of daily take and to transport the funds to accounting.

Fact-finding eliminated the possibility of forced entry, the duplication of keys, ex-employees with keys or faulty equipment, leaving suspicion to rest squarely on either security personnel or the accounting department.

Interview Revelations

Guards were first interviewed, who revealed that the daily deposit did not go directly to accounting, as policy suggested, but that the bag of coins was brought to the security office to be counted before it was brought to accounting.

And, you may ask: “Who might have authored that policy change?” John, the Director of Security did. And why? “Just because he wanted it that way.”

Further questions posed to cafeteria and gift shop staff revealed that John always paid for everything he bought with what seemed to be an endless supply of coins.

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This lead to a self-evaluating question: “Why let my lack of experience and formal training in the art of interrogation get in the way of a good investigation? Besides, how hard could it be to get a confession?”

What followed should have been a seamless interview that lead to an interrogation, a confession and concluded with the laying of criminal charges.

The Bungled Interview

John arrived at my office under the pretext of discussing my findings and to discuss other investigative options.

Producing my audio recorder and, at the same time, asking whether he minded that I record the conversation caused an odd reaction for a man who was still under the illusion of helping to further an investigation. John moved his chair back from the recorder and reared back on the chair’s legs to put distance between himself and the obvious threat. That single act in any interview could be an indicator of fear and of guilt on some level.

I opened with a flood of irrefutable findings, including statements from security guards, cafeteria employees and gift shop workers, while he nodded in agreement to the onslaught of evidence being presented against him. The coup de grâce occurred when I produced a series of photographs taken by his own security supervisor who had taken photos daily showing a depletion of cash from the bag of money being held in John’s own desk drawer.

Dogged Denial

When it was over, John quietly leaned forward staring at the floor with rounded shoulders and clearly defeated. What was a normal speaking voice moments prior now dropped to barely a whisper in order to avoid being heard on tape. John denied. Yes, he denied everything.

No argument I could make, nor anything I said or did, would convince him to admit to the thefts. John left my office in tears, without admission, professing ill treatment, threatening legal action and promptly submitted his resignation to the hospital citing indignation and hurt feelings.


There were so many lessons learned from this interrogative failure but the most important was my clear lack of training and expertise. All the signs were there, but I failed to secure the admission of guilt. Subsequent training and courses have rendered the mistakes of that incident painfully obvious.

Guy Parent
Guy Parent

Owner/President Corporate Investigation Services

Guy Parent founded CIS in 1988 with well over 12,000 case files of experience to draw from. CIS provides investigations for public and private companies through Corporate Investigation Services and is dedicated to pre-employment Screening through Corporate Inquiry Systems. Guy’s 30 years of devotion to the Protection and Investigation industry serves his clients in the areas of Labour Strike Crisis Management, Risk Assessments, Forensics, Covert CCTV and Surveillance while also providing Client Training Seminars.

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