Law Enforcement Operations, Patrol, and Investigations
Patrol as the Backbone
Patrol is the primary crime-prevention and community-contact function. Understand patrol styles-directed, preventive, and community-oriented-and the concept of hot spots. Officers must master the BOLO process, radio discipline, and the elements of a proper field interview: identify, separate, observe, and document. Report writing must be accurate, chronological, and factual; conclusions belong in the narrative only when supported by observations.
Investigative Fundamentals
Investigations follow a logical sequence: secure the scene, render aid, identify and separate witnesses, canvass, collect and preserve evidence, and maintain the chain of custody. Know the difference between testimonial and physical evidence and the importance of chain of custody documentation. Understand corpus delicti-the body of the crime-and that a confession alone is insufficient without some independent evidence the crime occurred.
Crime Scene and Evidence Handling
Preserve the scene, minimize contamination, and document before you disturb. Photograph before collecting, package items separately, and label with date, time, collector, and location. Biological evidence requires special handling to prevent degradation.
Traps and a Rule of Thumb
Questions confuse interview (witness/suspect, non-custodial) with interrogation (custodial questioning designed to elicit incriminating responses). They also test whether you know that chain-of-custody breaks can render evidence inadmissible. Do not assume a suspect's statement is enough to convict.
Worked example: A burglary scene shows a broken window, footprints, and a latent print. The correct order is: secure and render aid, photograph the undisturbed scene, then collect-prints before fragile trace, trace before heavy items-documenting each transfer.
Rule of thumb: Document first, collect second, package separately, and log every hand that touches the evidence.