Chapter Overview

        The business of the police is people. While police rely on people to report and help solve crimes, every facet of police work is concerned with the problems of people. The job of the criminal investigator is no exception. People and the information they supply help accomplish investigative tasks; collecting information is the key investigative task of police work. Roughly 90 percent of investigator's activity involves gathering, sorting, compiling, and evaluating information. The investigator cannot function without information, and information cannot be obtained without help from the people. In short, people are the most valuable resource in any criminal investigation.

        In every criminal investigation process, interviewing and interrogation are the most important means to obtain needed information about a crime. Both require a combination of art and skill that must be cultivated and practiced. Not all people who possess information needed by the investigator are willing to share it. This is true in both interviews and interrogation. Witnesses may have various motivations and perceptions, for example, that could influence their responses during an interview. These motivations and perceptions may be based on either conscious choices or subconscious stimuli. In addition, gaining information from specific demographic groups like the elderly and children requires unique skills on the part of the investigator. Situational characteristics such as the time and place of the interview/interrogation may also create challenges to eliciting knowledge about a particular case. Each of these conditions must be effectively addressed in both an interview or interrogation setting. The successful interviewer/interrogator must fully understand the techniques of interviewing and interrogation and have the ability to evaluate the psychological reasons why people are willing or reluctant to impart information.

        The interviewer/interrogator/investigator's own capabilities and limitations must be recognized. Personality and the manner in which interpersonal communications are handled can greatly influence the quality and quantity of information obtained. He/she must be able to convey empathy, sympathy, anger, fear and joy at various times, as needed but must always remain truly objective. It is important that the interviewer/interrogator keep an open mind, and is receptive to all information, regardless of its nature. Above all, the successful interviewer/interrogator must have an insatiable curiosity.