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The use of the personal identifier “I” signals truthfulness. Using the personal identifier “I” indicates a person is committed to what they said or wrote. Liars often cannot commit to false information and omit the personal identifier “I” when they speak or write. In many instances, liars will blend the truth with deception resulting in the presence of the personal identifier “I” in truthful statements and the omission of the Personal Identifier “I” in deceptive statements.
People who tell the truth retrieve information from their memories. Deceptive people either make up facts or modify facts from truthful events previously stored in their memories. When fabricating information or facts, liars mentally rehearse their stories in the present tense. When they are satisfied that the fabricated stories are plausible, they must then translate the present tense information or facts into the past tense to simulate a truthful narrative. Liars often fail to translate all the present tense verbs into the past tense and subconsciously speak or write narratives using both past tense and the present tense verbs. Information or facts spoken or written in the present tense suggest deception.
One exception to this rule is that when people recount personally traumatic events, they often use the present tense because they are reliving the events in their minds as they retell the story. Another exception is that people sometimes use the past tense expressions when referring to the present tense. For example, When first meeting a person, people often say, “What did you say your name was?” instead of “What is your name?” When buying a airplane or train ticket, people often say, “I was looking for a ticket to Chicago” instead of “I am looking for a ticket to Chicago.”
On January 28, 2003, Diane Sawyer interviewed Scott Peterson, who was later convicted of killing his wife, Laci and her unborn son, on Good Morning America. The following is an excerpt from that interview:
SAWYER: Tell me about the state of your marriage. What, what kind of marriage was it?
PETERSON: God, I mean the first word that comes to mind is—you know—glorious. I mean we took care of each other very well. Uhm—she was amazing — is amazing.
SAWYER: You haven’t mentioned your son.
PETERSON: Hmm—that was—it’s [it is] so hard.
Peterson used the past tense “was” to describe his relationship with Laci, quickly corrected himself, and used the appropriate tense. The quick change in tense suggests that Peterson realized that he made a mistake and corrected it because he wanted to portray himself as an innocent person. Peterson made the same mistake when he talked about his unborn son. The change and the immediate corrections support the hypothesis that he killed or, at least, had knowledge that his wife and unborn son were dead.
When deception is suspected, each sentence a person speaks or writes should be examined for the use of the First Person Simple Past Tense formula to determine if the speaker or writer is committed to the activities they are relating. The lack of the First Person Simple Past Tense does not always signal deception but does identify areas in the spoken or written communications that require further inquiry, especially if the omission of the First Person Simple Past Tense deviates from the speaker or writer’s baseline.
