Page:Protective Intelligence and Threat Assessment Investigations - A Guide for State and Local Law Enforcement Officials.pdf/44

 the interviewer to areas relevant to whether the person poses a threat to particular targets.

Interviews can provide investigators with valuable information about subjects' thinking, motives for engaging in the behavior that initially brought them to the attention of the authorities, behavior that might be of concern, and leads for further investigation. Interviews may corroborate subjects' statements and be the basis for judging their veracity. Interviews also give subjects the opportunity to tell their personal stories, to be heard, and to reassess and redirect their behavior away from activities that concern investigators.

If at all possible, an interview should be conducted in a subject's "natural environment"—for example, at home—permitting the investigator to observe and gather nonverbal information and evidence that is relevant to the investigation, such as writings, pictures, and weapons that are within sight. Also, the investigator will learn about the subject's overall lifestyle and personality traits.

Investigators must sometimes interview persons who appear to be mentally ill. Such interviews often require special patience. Investigators should remember several basic principles regarding interviews with mentally ill subjects:

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 * Any subject, including a mentally ill subject, will behave in accord with how he or she perceives reality. Thus, to understand how a mentally ill subject has behaved or may behave in the future, investigators must learn how the person perceives reality. For example, a subject who believes that aliens are controlling his mind and telling him to attack the Governor may feel that he is being forced to stalk the Governor, even though he sees himself as generally law-abiding and knows that attacking the Governor is illegal. An investigator who dismisses this thinking as crazy, concluding that the subject is unlikely to act, and who stops the interview may not explore whether the subject has made efforts to get a weapon or travel to sites where the Governor is likely to be.