Since past behavior is the best indicator of future performance, the background investigation is essential in assessing the suitability of a candidate for police work. The background investigative process should analyze the application information provided by the applicant and verify the information to ensure the truthfulness of the applicant's statements. Few departments can afford a full-time background investigation staff. Typically, background investigations are assigned to internal affairs investigators, field training officers, criminal investigators, or academy staff members. Regardless of who conducts investigations, they must be trained to understand the relationship between their inquiries and the job qualifications, to avoid the use of discriminatory criteria, and to avoid being overly intrusive in the investigation. An assessment of previous behavior should focus on previous job performance, driving record, and interviews with persons familiar with the candidate's behavior and personality characteristics. Background investigations should require at least 40 hours, be completed before the hiring decision is made, be conducted by departmental personnel rather than an outside agency, and be performed under consistent guidelines.