What does "interrogation" refer to in law enforcement?

The term "interrogation" in law enforcement specifically refers to the questioning of a suspect or witness by police officers. This process is a crucial part of criminal investigations as it allows law enforcement to gather information, clarify details surrounding a case, and potentially obtain confessions or admissions from suspects. Interrogation techniques can vary, and they require careful adherence to legal standards to ensure that the rights of individuals are respected.

In this context, the other choices do not accurately define interrogation. The formal arrest of a suspect involves placing an individual in custody, which is a separate legal action from the questioning process. The questioning of witnesses by a judge pertains to courtroom procedures and typically does not involve law enforcement directly. The gathering of physical evidence relates to the collection of tangible items that may support an investigation, rather than the process of asking questions. Therefore, the choice indicating that interrogation refers to the questioning by police accurately captures the essence of what interrogation entails in law enforcement.