When conducting a telephone interview, the investigator is always trying to assess the credibility of the information that the subject is providing by comparing the information to known case facts and evidence, as well as evaluating the verbal characteristics of the subject’s responses. In part Two of this Telephone Interviewing Techniques Investigator Tip we will focus on the verbal and paralinguisticbehaviors that the investigator should listen for as indications of truth or deception.
Within the scope of detecting deception, there are two broad inferences that are made through behavioral observations. The first involves inferences of “guilt” or “innocence,” that is, “Did this person engage in a particular criminal act?” The second involves inferences of truth or deception, that is, “When this person says such and such, is he telling the truth?” For case-solving purposes, it is important for an investigator to appreciate the distinction between “guilt” and “lying.”
Consider the following exchange during an interview:
Q: “Have you ever thought about setting fire to one of your properties for the insurance money”?”
A: “Well sure. Anybody in my position would have those thoughts.”
This suspect’s verbal response to the investigator’s question may be completely truthful, but the content of the response certainly infers a strong likelihood of guilt with respect to setting one his properties on fire.
To appreciate the nature of these inferences, it must be realized that communication occurs at three distinctly different levels:
- verbal channel—word choice and arrangement of words to send a message
- paralinguistic channel—characteristics of speech falling outside the spoken word
- nonverbal channel—posture, arm and leg movements, eye contact, and facial expressions
In this telephone interviewing Investigator Tip we will focus on verbal and paralinguistic behaviors.
When evaluating a suspect’s behavior for detection of deception purposes, it is important to remember that there are no unique behaviors associated with truthfulness or deception. The behavioral observations an investigator makes of a suspect do not specifically correlate to truth or deception. Rather, they reflect the subject’s internal emotional state, cognitive processes, and internal physiological arousal experienced during a response. The emotional states most often associated with deception are fear, anger, embarrassment, indignation, or hope (duping). For the truthful individual the cognitive processes may reveal concern, helpfulness, and confidence versus (for the deceptive) offering an unrealistic explanation for the crime, being defensive, or being overly polite.
It is critical at the outset of any interview to establish the subject’s normal behavioral patterns. Everyone is unique and has their own patterns of speech, vocabulary, rate of response, tone of voice, etc. Consequently, at the outset of each interview the investigator should spend several minutes discussing nonthreatening information (casual conversation or collecting biographical information) so as to establish a behavioral baseline for the particular subject. Then, as the interview progresses and the subject exhibits behavioral changes when the issue under investigation is discussed, these changes may take on added significance.
Evaluating the Subject’s Attitudes
Once an investigator advises the subject as to the purpose of the interview the subject knows whether or not he committed the act in question. This underlying knowledge of “guilt” or “innocence” will cause the suspect to form fairly predictable thoughts and perceptions, which are collectively referred to as the person’s attitudes. These attitudes form the primary basis for inferences of guilt or innocence. They also affect the subject’s verbal and paralinguistic behaviors.
Some attitudes are common to both truthful and deceptive subjects. As an example, both may appear anxious or apprehensive during the interview, albeit for different reasons. The deceptive subject is fearful that the investigator may detect his guilt, whereas the truthful subject may be fearful that the investigator will not believe him, or he may fear retaliation from the guilty person whom he may implicate to the investigator.
The following are attitudes most commonly seen in truthful or deceptive subjects during an interview.
- Spontaneous versus Guarded. The truthful subject generally offers lengthy, free-flowing responses during an interview and volunteers information. The truthful subject’s answers are “on time” – there is no delay or hesitation when answering direct, fact related questions. The deceptive individual may offer delayed, short responses containing only minimal information. This guarded attitude may represent the guilty subject’s caution in possibly being caught in a contradictory statement or merely be an anxiety-relieving effort to avoid telling unnecessary lies in response to a question.
- Sincere versus Insincere. The truthful subject openly expresses appropriate emotional states. If the subject is upset, anxious, or concerned, these emotions will be communicated on all behavioral channels. A deceptive subject may come across as phony during an interview, often being overly friendly and overly polite to the investigator. The insincere subject sells his innocence as if it is a product, whereas the sincere subject states his innocence as an irrefutable fact.
- Helpful versus Unhelpful. Most truthful subjects are helpful. During an investigation most truthful individuals go through a thought process called “playing mental detective.” They know that they did not commit the crime so they ask themselves, “Who probably did?” “Who do I know who did not do this?” “Why was it done?” “How was it done?” Consequently, during the investigative interview the innocent subject is comfortable discussing possible suspects, speculating about possible motives to commit the crime or how it might have been committed. On the other hand, the guilty subject does not play mental detective as he already knows who committed the crime. Because of this he is uncomfortable theorizing about possible suspects or motives. He does not like to talk about specific details of the crime he committed even if the questions are posed in a hypothetical sense.
- Realistic versus Unrealistic. Truthful subjects are realistic in their assessments of the crime. It is not threatening for them to conclude that the missing merchandise was probably stolen, that the fire next door was arson, or that someone did have sexually assault their neighbor’s daughter. On the other hand, deceptive individual would love to convince the investigator that the merchandise was mistakenly shipped to another location, that the fire next door was electrical in origin or that the young girl next door was making up a story.
- Concerned versus Unconcerned. The truthful subject comes across as being very concerned during an interview. He/she approaches the interview in a serious manner and pays close attention to the interviewer’s questions—after all, their reputation, possible livelihood, and freedom are at stake. The deceptive subject, however, may approach the interview quite nonchalantly and downplay the significance of being a suspect in the investigation. The guilty individual may engage in levity or answer questions inappropriately because he is not paying close attention to the interviewer’s questions. A telling difference between the truthful and deceptive subject is that the innocent suspect will have given much thought about the guilty person—who that person might be, why and how he committed the crime; he will express harsh judgments toward the person guilty of committing the crime. The guilty suspect has not gone through that same thought process. When asked to speculate about the person who committed the crime, the guilty suspect may simply state that he has not given that issue much thought; he feels uncomfortable providing insight for the crime he committed. For much the same reason, he is unlikely to express harsh judgments against the person who committed the crime.
- Cooperative versus Uncooperative. A truthful subject perceives the interview as an opportunity to be exonerated, either by answering the investigator’s questions truthfully or by providing information helpful in catching the guilty person. Consequently, innocent suspects generally agree to be interviewed, will keep their interview appointment, and will provide reasonable documentation (such as phone bills, parking stubs, bank statements, or computer records) to support their statements. During the interview they openly respond to the investigator’s inquiries and make no attempt to rush the process. The guilty suspect may offer weak excuses as to why he is unavailable to be interviewed or fail to show up for scheduled interviews. During the interview itself, the guilty suspect may present a variety of complaints, ranging from the length of the interview to the fact that he has already related his story to an investigator. The guilty suspect is unlikely to follow through with promised documentation requested from the investigator.
Evaluation of Verbal Behavior
A subject who is properly socialized and mentally healthy will experience anxiety when he lies. This anxiety may result from internal conflict the suspect experiences because he knows that it is wrong to lie, or from fear that his lie will be detected. Whatever the source, during an interview lies result in anxiety, and many of the behavior symptoms revealed by a deceptive suspect represent his conscious, or preconscious, efforts to reduce this internal anxiety. This fundamental concept forms the basis for evaluating a subject’s verbal and paralinguistic behaviors.
When a deceptive subject is asked a direct question during a telephone interview, he has essentially several verbal response options from which to choose: deception, evasion, omission or truth.
A truthful response (“Yes, I did”; “No I didn’t”) does not cause internal anxiety. However, as the response moves further from the truth, the subject experiences more internal anxiety as a result of his deception. An omissive response implies non-involvement without the use of words. The use of nonwords such as “uh uh” represent an omission in that the suspect is implying noninvolvement without actually stating it.
The next level, evasion, uses words to imply noninvolvement without stating it. The suspect is not lying but also is not accepting any physical responsibility within his response. Therefore, the subject experiences more internal anxiety through evasion - “Now why would I do something stupid like that?”- than omission. Finally, the subject may choose to outright lie to the question – “No I did not.” A deceptive response is associated with the greatest level of internal anxiety.
With respect to verbal response options, if given a choice the guilty subject would much rather engage in evasion or omission than outright deception. The truthful suspect, who experiences no conflict or fear within his response, expresses his responses in a definitive and emphatic manner. The guidelines below are useful when evaluating a suspect’s verbal response to an interview question.
Truthful subjects respond to questions directly; deceptive subjects may answer evasively.
Consider the following two responses to the question of a homicide suspect, “When is the last time that you saw Tom Smith?”
- It was Friday at about 5:30. I drove Tom home from work because we car pool and that was my night to drive. I dropped him off at his house right around 5:30. That’s the last time I saw him alive.
- Tom and I car pool and Friday was my day to drive so I drove him home from work and I arrived at his house right around 5:30.
Response 1 offers a definitive response to the investigator’s question. From this response, the investigator knows exactly what time the subject is claiming to have last seen the victim. The second response merely implies that the last time the subject saw the victim was 5:30. This response leaves open the possibility that he saw the victim later that night, that he came into the victim’s house with him, or that he never actually dropped the victim off. Deceptive subjects rely extensively on implication during verbal responses. The subject hopes that the investigator will make unwarranted assumptions about what he probably meant or intended to say.
A second common type of evasive response is answering a question with a question. When a subject responds, “Why would I do that?” “Do you think I would risk going to jail by doing that?” or “Don’t you think that would be a little ridiculous of me?” the investigator must recognize that the subject has not offered a definitive denial.
A final type of evasive response is called “lying by referral.” Consider the following dialogue in which the subject is guilty of stealing a car:
Q: “Did you steal a blue Monte Carlo last Saturday night?”
R: “That other cop already asked me that. Like I told him, I don’t know nothing about this.”
Even though this subject did steal the car, he has not lied at all during his response. Another police officer did ask him that question and the subject told the officer that he did not know anything about the stolen car. What the suspect failed to include in his response is that he lied to the other officer. Whenever a response is predicated on some earlier communication, such as, “Like I wrote in my statement,” “As I previously testified. . .,” “You already asked me that and I told you before. . .,” the investigator should suspect lying by referral.
The following list of phrases and their interpretations should primarily be used to stimulate follow-up questions during an interview, rather than as a clear indication of deception. Some of the guidelines list as (1), the most typical interpretation and (2), a secondary consideration. A good exercise is to monitor your own use of these phrases. After you have used one of them, ask yourself why you chose to use it and what another person could have asked you at that point during a conversation to learn more about your answer. As with all behavior symptoms, it should be remembered that there are no universal words or phrases that are always associated with truthfulness or deception and that the context in which a phrase is used is a critical assessment.
"As far as I can remember..."
"To the best of my knowledge..."
"If I recall correctly..."
"At this point in time..."
(1) I am not 100% certain of what I am saying.
(2) I am blaming my poor memory for not telling you the complete truth.
"The next thing I knew..."
"Before I knew it..."
(1) I am leaving something out of my account.
(2) This happened very quickly
"To be honest with you..."
"To tell you the truth..."
I have not been completely honest (truthful) with you up to this point (usually through omission).
What I am about to tell you is only part of the truth.
"As crazy as it sounds..."
"Not to evade your question, but..."
"You probably won't believe this..."
I want you to accept my response even though it is crazy, is evasive or is not believable.
"As I told the other investigator..."
"Like I wrote in my statement..."
"Earlier I told you..."
"As I previously testified..."
(1) I don't want to lie twice about this.
(2) I am frustrated having to go through this again.
"As God is my witness..."
"You've got to believe me..."
(1)You shouldn't believe what I am about to say.
(2) You probably won't believe what I am about to say.
"I can't remember"
"I can't tell you..."
"I can't help you out."
(1) It is not in my best interest to remember, to tell you, or to help you out.
(2) Because of some intrinsic reason (embarrassment, fear, anger) I don't want to talk about this.
"Most likely I..."
"It would be typical for me to..."
It is possible that something other than what I said in my response really happened.
"My answer would be..."
"I would have to say..."
(1) I am offering an estimation and don't know for certain.
(2) If I tell you what happened I would incriminate myself.
I am offering an opinion, but have no specific proof to back up my position.
I am telling you something that I personally witnessed.
"I don't know"
"I don't remember"
(1) The subject has no knowledge or memory of the event.
(2) The subject is being guarded and does not want to expand on his answer.
"There's no doubt in my mind..."
"I'm absolutely sure..."
(1) The subject is accepting full responsibility for his response and is confident in it.
(2) The subject is purposefully being too certain in his response to fend off further questions.
Evaluation of Paralinguistic Behavior
There are a number of speech characteristics during a subject’s verbal response that can alter the meaning of the words. As a common example, we have all heard a friend or coworker make a sarcastic remark. Based on the pitch or tone of the comment, we know that the person does not really mean what was said. The paralinguistic channel of communication is under less conscious control than the verbal channel. Consequently, paralinguistic cues during an interview may be the best source of detecting deception for a criminal investigator.
Response latency. Response latency is defined as the length of time between the last word of the interviewer’s question and the first word of the subject’s response. Clearly, delayed responses to a straightforward question should be considered suspicious. A subject should not have to deliberate on how to respond to a question such as, “Did you falsify the signature on any of these company checks?”
Deceptive subjects are often consciously aware of their delayed latencies to the interviewer’s question and may attempt to disguise the delay through stalling tactics. A common strategy in this regard is to repeat the interviewer’s question or to ask for a simply worded question to be clarified.
Early responses. Another category of paralinguistic behavior related to response timing is a response that is offered before the interviewer finishes asking his question. A truthful subject who is somewhat nervous may offer early responses, especially at the beginning of the interview. This is simply the result of the subject’s general anxiety. Such early responses coming from the truthful subject will be repeated after the interviewer finishes asking his question.
Early responses emanating from the deceptive subject often are not repeated. Once the subject voices his denial while the interviewer is still asking the question, in the subject’s mind he has answered it, even though the investigator has not completely finished asking the question. It is an especially reliable sign of deception when an early response occurs during the middle or end of an interview; by that time, general nervous tension from the truthful subject should have subsided and the early response is likely coming from the deceptive person anxious to get a prepared lie out of his mouth.
Response length. Statistically, truthful subjects offer longer responses to interview questions than do deceptive subjects. The truthful subject wants to completely respond to the question and often volunteers more information than called for in the question. The content of the truthful subject’s more lengthy response will stay on track to the interviewer’s question; the truthful subject does not start out saying one thing and divert the interviewer’s attention away from his initial response by talking off the subject.
Conversely, some deceptive subjects may respond by offering just enough information to satisfy the investigator’s question. This subject is concerned that if he offers too much information, he may contradict himself or other evidence that exists.
Response delivery. The subject’s rate, pitch, and clarity during a response can either be consistent or inconsistent with the verbal content of what is being said. As a general guideline, when a subject is relating a truthful emotional account, his rate and pitch will increase as he relives the event. However, when rate or pitch decrease this may mean that the subject is editing information or is uncertain of what actually occurred. An alleged victim of a home invasion who relates the crime in a monotone, or even slows down his response delivery at certain points, is not offering a spontaneous account and fabrication or omission should be suspected.
A truthful subject wants the investigator to understand his responses and, therefore, will speak clearly and in an appropriate volume. A deceptive subject may mumble during a response or talk so quietly that the investigator has difficulty hearing the response.
Continuity of the response. A truthful response is spontaneous and free flowing but will maintain continuity in that one sentence, or thought, will naturally stem from an earlier one. A significant paralinguistic behavior of deception, however, is called “stop-and-start” behavior. In this instance, the subject begins his response in one direction but abruptly stops it and starts over again in a different direction.
In summary, in Part One of this Investigator Tip on Telephone Interviewing Techniques we discussed the structure of the interview:
Identifying the Interview Goals
The Structure of the Interview
Closing the interview
Documenting the interview
In Part Two we discussed the verbal and paralinguistic behaviors that can help the investigator evaluate the credibility of information provided by the subject including
Verbal Behavior Characteristics
For additional information on this topic see our 3-hour audio training program, Telephone Interviewing Techniques.
* Some of the text above is from our book, Criminal Interrogation and Confessions, 5th edition, 2013
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