In most instances, subjects will agree to answer an investigator's questions if the conversation occurs at the subject's home, place of business or over the phone. From an investigative perspective, however, it is far more productive to have the subject agree to come to the investigator's office for the interview. Once the investigator is alone with the subject in a controlled environment a structured interview can be conducted to assess the subject's probable involvement in the offense. If the subject's statements and behavior are indicative of innocence, the person can be eliminated as a suspect in the case. On the other hand, if the results of the interview suggest probable involvement in the offense, the investigator can move directly into an interrogation in an effort to obtain evidence of the subject's guilt in the form of a confession.

Legally, an investigator cannot compel a subject to submit to an interview. Therefore, persuasive tactics are often required to convince a subject to come to the investigator's office to be interviewed. This article will identify a number of principles designed to increase the probability that a subject will agree to submit to a voluntary interview. The focus here will be on non-custodial interviews where the investigator has not taken the suspect into custody and, therefore, no Miranda waiver is needed prior to questioning the suspect.

1. In general, be truthful about the purpose for the interview. For the subject to make a knowing and voluntary decision to be interviewed, he must know what issue will be discussed during the interview. There are two exceptions to this guideline. We believe that it may be proper to establish a false pretense for a non-custodial interview if (1) there is concern that the subject may destroy evidence or, (2) the subject represents a flight risk where the investigator would lose authority over the subject.

Consider an investigation where a bookkeeper is suspected of embezzling funds by altering computer invoices. Further, the bookkeeper has already discussed her pending retirement. If the bookkeeper is asked to come to the manager's office to be questioned about possible theft of company funds certainly she could delete the computer records of her embezzlement or resign from the company. It, therefore, may be advisable to arrange a private meeting with her under the false pretense of discussing how best to train her replacement when she retires. Once the interview begins the bookkeeper should be told that the true purpose for the interview is to discuss the results of an internal investigation that indicates diversion of company funds.

2. The investigator's description of the issue under investigation should be vague. For a number of reasons, specific details of a crime should not be revealed to the suspect. First, the investigator can assess the subject's possible involvement in the crime if, during the interview, the subject reveals information that only the guilty person would know. Second, details of the crime that only the guilty person would know can be used to corroborate a confession. For example, the following statement to a subject in a hit and run investigation contains too much information:

"Harry, last Saturday evening at 10:50 a white male named Paul Stone was struck by a silver Pontiac Grand Am outside the B&B tavern. The vehicle left the scene going north on Jackson Street. Witnesses reported that the driver of the vehicle was wearing a yellow windbreaker like the one you're wearing."

In addition, the investigator's description of the crime should avoid legal terminology. A husband who killed his wife during an argument is unlikely to voluntarily agree to meet with the investigator to be questioned about the murder of his wife. However, he may agree to be interviewed to provide further details surrounding her death. The following list offers non-descriptive terminology for various crimes:

Arson = to determine if the fire may have been intentionally started

Burglary = taking things from a car; entering a home

Fraud = discrepancies in paperwork; questions concerning a document

Murder= circumstances surrounding (victim's) death

Rape = had sex with; sex was not consensual

Robbery = took money from a clerk (liquor store)

Sexually touch = had contact with the child in a manner that upset her

Stolen deposit = missing deposit

Theft = shortages, mysterious disappearance

3. The investigator should establish a non-threatening pretense for asking the subject to be interviewed. The investigator must appreciate that neither innocent nor guilty suspects enjoy being interviewed concerning an act of wrong-doing and that some persuasion will be required to elicit a person's cooperation. In essence, the investigator must present the interview in a positive light. On the other hand, if the investigator approaches the subject as if there is little doubt that he committed the crime under investigation, the subject is unlikely to voluntarily agree to meet with the investigator for a session that essentially will be an accusatory interrogation.

A common non-threatening pretense is to bring up the interview as an opportunity to be cleared in the investigation. For example, when a group of employees each has access to a deposit that was stolen or a patient who was physically abused, it makes perfect sense to the employees that they all need to be interviewed in order to resolve the investigation. In essence, it is in the employee's best interest to agree to be interviewed as a means not only to be exonerated, but also to catch the guilty person.

Sometimes a non-threatening pretense will involve the subject's desire to obtain a specific goal. Consider a subject who submitted an insurance claim requesting $25,000 replacement value for his stolen vehicle. The investigator may explain that there are a couple of questions about the theft and that the quickest way to settle the claim would be for the claimant to come in for an interview. Similarly, when a specific accusation has been made, such as a student who claimed that her teacher sexually touched her during recess, the investigator can present the interview as a means to obtain the desired goal of being exonerated.

Under some circumstances establishing a reasonable pretense for the interview is more difficult. For example, a confidential informant may have named the suspect as one of several people involved in a recent home invasion or, on a hunch, the investigator may want to re-interview a previous suspect in a twenty-year-old homicide. Under these circumstances it may be necessary to establish a false pretense to persuade the subject to agree to be interviewed. To protect the informant's name in the home invasion case, the investigator might tell the subject that one of the victim's neighbors saw the suspect outside of the victim's home on the night of the crime. In the homicide case the investigator might establish a pretense for the interview based on "new forensic technology" which places the suspect near the victim around the time of her death. Another pretense could be that an acquaintance of the victim recently came forward with a letter the victim wrote shortly before her death that mentions the suspect's name.

Establishing a false pretense for the interview will almost always involve reference to some fabricated or distorted evidence connecting the subject to the victim or crime scene. This is always a risky procedure in that the subject may either call the investigator's bluff and ask to see the evidence or be scared off and refuse to come in for an interview. For these reasons, the investigator should carefully abide by the next guideline.

4. Do not overwhelm the suspect with evidence of his guilt. Most criminal suspects know that the polygraph technique is quite accurate and yet every day guilty suspects voluntarily agree to take a polygraph examination and subsequently confess after failing the examination. Why would a person risk having their crime detected by taking a polygraph examination? The primary reason for this is that the suspect believes he can "beat" the polygraph examination and, if he is successful in doing so, he will avoid the consequences associated with his crime.

On the other hand, if a guilty suspect believed that the polygraph technique was 99.9% accurate it is highly unlikely that he would agree to take the examination. Similarly, if the investigator brings up evidence that strongly points to the subject's probable guilt, the subject may well decide that his best chance to get away with his crime is to refuse to be interviewed. Consequently, any evidence used to persuade a subject to submit to an interview should not directly incriminate the subject. Rather, the evidence should indirectly connect the subject to the victim or the crime scene..

With this principle in mind, the following would be an improper use of evidence to persuade a subject to agree to be interviewed, "Jim, your DNA was found during the autopsy of the victim and we have your fingerprints from the inside of her apartment. I would like you to come in for an interview to determine whether or not you murdered her." Conversely, the following statement is much more likely to result in the subject agreeing to be interviewed, "Jim, I am in the process of talking to people who knew Mary Smith and I got your name from her address book. I have some of her co-workers coming in this morning but I'm free at 2:00. Would that be a convenient time to meet with me?"

The second statement offers a logical, yet non-threatening, connection between the subject and the crime. Because of this, the subject is more likely to agree to be interviewed not only because he believes that the investigator has no proof of his guilt but also because there are other subjects who have apparently agreed to be interviewed. This leads to the final principle.

5. If credible, relate that other suspects will also be interviewed. Another reason that guilty suspects agree to take a polygraph examination is that they do not want to stand out as being different from other suspects by being the only person not willing to take the examination. By surrounding a suspect with other real or fictitious suspects, it is much more likely that the person will agree to be interviewed.

If the investigator implies that the subject is one of many possible suspects in the case to be interviewed it reinforces the hope in the guilty person's mind that he may get away with his crime. To maintain the guise of innocence, the guilty suspect does not want to point the finger at himself by refusing to be interviewed.

In conclusion, it is generally not difficult to persuade innocent subjects to agree to be interviewed concerning someone else's crime. Generally innocent subjects agree to cooperate with an investigation in an effort to be exonerated and to help catch the guilty person. However, often finesse and even guile is required to persuade a guilty subject to agree to be interviewed.

A subject who is guilty of a crime must be convinced that it is in his best interest to submit to an interview at the investigator's location. Therefore, the investigator should present the interview in a positive light, perhaps as a means for the subject to be eliminated from suspicion. The investigator should make it appear that other subjects are being scheduled for interviews and not overwhelm the subject with incriminating evidence. The guilty subject agrees to be interviewed because he believes by doing so he will get away with his crime; the investigator should do nothing to dispel that hope.