Candidates who pass the initial testing phases move to the Background Investigation and Polygraph Exam phase. The Police Department conducts thorough background checks, including criminal and driving history records, educational and employment history, and personal interviews with various references. Candidates not eliminated during this investigatory process proceed to the polygraph exam, which evaluates truthfulness regarding provided information and involvement in illegal activities. The polygraph exam serves as an investigative tool and is conducted before the conclusion of the background investigation.