In order for a criminal case to go forward, police must gather evidence. This can occur either on the scene of a crime, where police officers are the first to arrive, or when they investigate crimes that have already occurred. Both types of investigations require the same basic processes, so let’s look at how law enforcement officials go about investigating a crime.
When police are on the scene of a crime, they may be able to stop it before it’s even committed. In that scenario, the perpetrator will be arrested and the police can focus on building a case that will stand up in court. But what about cases where the perpetrator is no longer at the crime scene? What is the process like for those situations?
As you can imagine, when police are investigating a crime they will be keen to speak with anyone who has knowledge of the incident. This includes people who have personal knowledge of the crime (such as family members), and witnesses. Witnesses are asked to provide statements about what they saw, heard, smelled or touched during the incident. This information is documented so that it can be shared with other police officers, detectives and prosecutors.
Police officers are trained to observe details and notice things that other people might miss. For example, they will note the position of weapons or blood stains to try to figure out what happened. They will also document their own observations and notes in a report. These reports will then be reviewed by other officers and detectives who can make decisions about pursuing lines of enquiry or not. If the investigation leads to a prosecution it will be passed to the Crown Prosecution Service for consideration. The prosecutor will decide whether to charge a suspect or not, and may recommend out of court disposal or community resolution.