A director of security for a top New York hotel recently pled guilty to setting a series of fires to shut down the building so that he could spend time drinking in the hotel rooms and also to bring negative attention to the hotels.

New York fire marshals arrested Mariano Barbosa on Friday. He was charged with setting five fires in the hallways, stairwells and emergency exits at the Yotel over the past two years. Before that, he did the same thing at his previous place of employment, the Soho Grand Hotel on West Broadway. Barbosa apparently set the fires so that the hotels would be shut down for repairs and he’d get paid time off on the job.

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Spotting Inconsistencies

And he might be gotten away with it. But the investigators who interviewed him were able to spot inconsistencies in his statements, tipping them off that he was trying to hide something.

A source quoted in a New York Daily News article said that Barbosa’s story “wasn’t matching up” and, when pressed, he admitted to setting the fires so that the hotels would be cleared out and he could avoid having to do anything at work.

Often, when an investigator is able to show a suspect that he or she has made contradictory statements, the suspect has no recourse but to confess.

The New York security director’s case highlights one of the best tools investigators can use during investigation interviews: the ability to spot conflicting information. There are several strategies that can help with this.

Open-Ended Questions

In his book, Interviewing and Interrogation, Don Rabon outlines the importance of asking open-ended questions:

“An open-ended question will normally provoke a more extended answer that includes more details,” he writes. “The interviewee is required to provide a narrative.”

In that narrative, an interviewee might say something that contradicts what he or she said earlier. The more open-ended questions the interviewer asks, the more chances the interviewee gets to provide conflicting information.

Documenting the Interview

No matter how much conflicting information suspect provide during investigation interviews, however, spotting and pointing out inconsistencies relies on having an accurate recall of everything that has been said. For this reason, it’s important to have a reliable record of the investigation interview.

There’s considerable debate over whether or not an investigator should take notes during an interview, whether interviews should be recorded, or whether a third party should be present specifically for the task of note-taking. A third-party note-taker frees up the investigator to concentrate on having the conversation with the interviewee. This is important for rapport-building, but a recording device similarly frees the investigator to interact fully with the person being interviewed. Some argue that taking notes during an interview shows that the investigator is listening and considers the information to be important enough to write down.

Whichever theory you subscribe to, the important point is that there must be an accurate record of what is said. And this record can provide, as it did for the New York fire marshals who interviewed Barbosa, the perfect piece of evidence that an investigator needs to prove an interviewee is lying.