Police investigations are a crucial part of the criminal justice system, and are conducted by specially trained detectives. A good investigation will follow all reasonable lines of enquiry to gather material that points both towards and away from a suspect. This will help to establish whether a criminal offence has occurred and determine whether that person should be charged with the crime or referred for a community resolution.
When a police officer is investigating a criminal offence, they will follow strict legal guidelines to ensure that all avenues of inquiry are explored. They will also use a range of investigative tools, including interviews and interrogations, to help them build strong cases for prosecution.
A key tool that police investigators use is the crime scene. When officers arrive at the scene of a reported incident, they will document all aspects of the scene to protect the integrity of any evidence. This will include taking photos and measurements of the scene, as well as obtaining any physical items that may have been left behind.
Then, they will interview witnesses to find out what they know about the incident. If a witness is unable to give their statement in English, or if they are deaf or hard of hearing, the police will arrange for an interpreter. The police will let the witness know where, when and how long they will be interviewed.
Detectives often use a range of other tools, such as social media searches and the use of warrants to obtain an individual’s financial and personal records from businesses or their partners. If they are investigating a serious crime, such as a drug offence or pornography, investigators may even go undercover to gather information and evidence. Learn more about police investigations and other topics in the field of law enforcement in AMU’s online criminal justice degree programs, including forensic science, U.S. law enforcement, and law enforcement leadership.