When we arrive and begin to investigate an incident, starting our investigation, we gather the facts. We determine the victims, witnesses, and suspects. We try to eliminate the people who were not involved in the incident.
One of the tools we use to help eliminate possible suspects is to ascertain their alibi. True alibis are usually easy to verify with a witness, a video, or other concrete information. The harder alibi to prove or disprove is where the subject was alone or at a function where no one would remember them — watching a movie in the theater, hiking in the woods, or jogging in the park. In these cases, we would talk to the people there — look for video or other information to prove the alibi.
Unfortunately, a failure to prove the alibi is not proof the subject committed the crime. Our goal is to break the alibi.
Breaking the Alibi
The basic principle of breaking the alibi is simple — it is getting the subject to change their story. When a truthful person tells you their story, it is the only story they have to tell. When we challenge them, they will not change the story. They may give us additional information, but it will not conflict with their alibi story.
If we continue to push a truthful person, insinuating they are not telling the truth, they will become angry. A truthful person has no place else to go. Their story is the only one they have to tell.
A person who has constructed a false alibi has to put together a fictitious story about where they were or why it was not them that committed the crime. The problem with this is, it is very hard to construct a story that takes into consideration every possible element. When the subject is presented with an unknown element that challenges their story, they have to make up more lies to accommodate the new information.
There are two ways to present your challenging information. One is evidence that would put them at or near the scene, when they have specifically stated they were not there. The other is to present information about the alibi location where they claimed to be. It is fictitious information the subject would easily be able to challenge, if they were really there.
The current fascination with the crime drama works in our favor — it educates the viewer to the vast resources available to the criminal justice community in solving crimes. When we present our evidence to break the alibi, the most important element is the acceptance on the part of the subject that our story is true.
Before you can introduce your conflicting evidence, you must pin down the subject’s alibi. Lock in where they were, what they were doing, and what they were not doing. Once you have established their alibi, you can present the possibility of conflicting information and ask them to explain the conflict.
Lead in by telling the subject about the possible evidence. Take the time to explain the existence of the evidence — it is something the subject would not be aware of. It is important that you convince the subject of its existence.
Evidence from the Crime Scene
The video camera is one of the best candidates to put the person at the scene. In today’s world there are cameras everywhere, including one in almost everyone’s pocket in their cell phone. Whatever evidence you present, however, ensure it is a possibility. For instance, if you use the existence of DNA evidence, you will need the possibility that a substance containing DNA was left.
When you present the evidence and ask the person if it will put them at the scene, use an off-hand demeanor, as if you believe the subject is not the perpetrator and there is a reasonable explanation for the evidence that shows the subject was there.
For example, in a case where the subject states he was nowhere near the location of the offense, you present the fact there is a camera that is positioned to capture the location where the suspect was seen. Ask the subject if there is any reason why they would be on the video, in a manner that shows you are open to a reasonable explanation.
After you ask the question, pause and give the subject time to think. You have just changed the dynamics of their lie and they will have to fabricate a reason why they were there. They will have to adapt their story to include the new facts you have just introduced.
If the person is telling the truth and was not involved in the offense, their answer should be fairly quick: They will probably state the evidence will show they were not there.
Evidence from the Alibi Location
The second example is where you introduce false information at the location where the subject claims to have been, instead of at the crime scene. The buildup to the presentation is the same — establishing rapport, locking in the alibi, and casually presenting the false evidence. In this case, however, you will fabricate an incident at the location where the subject claimed to be.
After presenting the fabrication, ask a question the subject should be able to answer, if they were really there.
If they say they were watching a movie on TV, say that during the movie there was an interruption for an emergency broadcast. Ask what the broadcast was about. If they remember the broadcast but not the subject, they are lying.
If they claim they saw a movie at a theater, say a person started having problems breathing. The house lights were turned up and the person was escorted out. Ask if it was it a man or a woman. If they claim to remember the incident but not the sex, they are lying.
Remember, if the subject does not change their story, that does not mean they are innocent. It merely means they did not change their story. When the person does change their story to accommodate your new and fictitious evidence, though, it means they were involved. This would single them out as a suspect for your investigation and ultimately an interrogation.