What is the investigation process?

Forensic officer examining a window

Once a crime has been reported to the MPS an officer will carry out an initial investigation, this will always happen, however a crime is reported.

The below information briefly outlines the many stages of a police investigation, from the initial investigation when a crime is first reported, to the investigative assessment and then through to the three possible outcomes of any investigation.


Initial investigation – this will involve a review of witnesses, scenes, CCTV and all other available evidence such as any forensic samples and any relevant local knowledge. Following this the crime will be entered into the MPS crime recording system before the end of the officer's shift. The victim will then be issued with a crime reference number within 36 hours of the initial investigation.

Investigative assessment – after the initial investigation the crime details are forwarded to the Crime Assessment Unit for an investigative assessment to be completed. A decision will then be made whether to transfer the crime to an investigating officer for further investigation or not. This assessment will take into account the following:

  • Seriousness of the offence
  • Likelihood of solvability (e.g. availability of evidence)
  • Level of resources required proportionate to the seriousness of the offence

The victim will then receive a letter or email notifying them of the result of the assessment. There are two possible outcomes at this point.

1. Investigation will be closed – this does not mean that the crime is not important or permanently closed as the MPS will keep all details on record and refer to the report when investigating other related crimes or trying to identify stolen property. The information you provide forms a vital part in deciding where and when to allocate police resources.

2. Crime transferred for further investigation – an investigating officer is assigned and he/she will be responsible for investigating the crime. This officer will be able to provide the victim with specific updates regarding the progress in the case.  The method of contact and frequency of communication will be agreed with the victim by the investigating officer.

Further investigation – if the crime is transferred for further investigation the investigating officer will carry out enquiries including:

  • Taking statements from the victim and any witnesses, which is a formal means of recording personal accounts of the crime
  • Arresting and detaining any identified suspects and formally interviewing them at a police station

After conducting interviews the suspect(s) may be bailed to return to the police station at a specified date. This allows the investigating officer more time to make further enquiries. At the end of the investigation there are three possible outcomes for the suspect(s).

1. Charged – the suspect is formally told that they will be sent to court and what law they are alleged to have broken.

2. Cautioned – an official warning given in some circumstances. If the suspect is brought to court within the next three years the court can take this warning in to account when sentencing them.

3. No further action – if there is insufficient evidence to charge or caution a suspect, no further action will be taken by police.