Which of the following categories does NOT belong to police/suspect encounters?

The category that does not belong to police/suspect encounters is investigations. Police-suspect encounters typically involve direct interactions such as voluntary encounters, detentions, and arrests, which are defined by the level of coercion involved and the legal implications of each.

Voluntary encounters occur when a police officer engages with an individual who is free to leave and is not being compelled to respond. Detentions involve a temporary seizure of an individual based on reasonable suspicion, allowing officers to ask questions or conduct a brief investigation without making an arrest. Arrests are more formal interactions where law enforcement takes an individual into custody, indicating that the officer has probable cause to believe a crime has been committed.

Investigations, on the other hand, usually refer to a broader process that may involve gathering evidence, surveillance, or conducting interviews over a period of time, and do not specifically categorize an encounter between a police officer and an individual. This process can include elements of voluntary encounters, detentions, or arrests, but it is not a direct type of encounter itself.