How Long Do the Police Have to Investigate a Crime in the UK?
If you are wondering how long the police have to investigate a crime in the UK, the short answer depends on the type of offence. For summary-only offences, which are generally dealt with in the magistrates' court, the prosecution must begin court proceedings within 6 months of the offence. For either-way offences (offences that can be tried in either the magistrates' or Crown Court) and indictable offences (the most serious crimes tried exclusively in the Crown Court), there is generally no statutory time limit on the investigation itself. A serious criminal investigation can, in principle, remain open for a prolonged period where there is no statutory time limit.
Below, we explain the rules in detail, why investigations can continue for years, and what you can do if you believe delay is damaging your position.
The 6-Month Rule for Summary Offences
Section 127 of the Magistrates' Courts Act 1980 sets a time limit for commencing proceedings for most summary offences: a magistrates' court cannot hear an information unless it is laid within 6 months of the date the alleged offence was committed.
What does 'laying an information' mean?
This is the formal step of beginning proceedings in the magistrates' court, not when the police begin an investigation or arrest a suspect. If the time limit of 6 months has passed and proceedings are then begun, the case is generally time-barred, and the prosecution cannot proceed.
Common examples of summary-only offences covered by the 6-month rule:
- Common assault (s.39 Criminal Justice Act 1988), subject to specific exceptions, including certain domestic abuse cases
- Most road traffic offences, including speeding, driving without insurance, and driving without a licence
- Section 5 of the Public Order Act 1986 offences
- Criminal damage where the value does not exceed £5,000
- Being drunk and disorderly in a public place
Important: Some statutes create their own time limits that override or extend the 6-month rule. Some regulatory offences have different statutory limitation periods or rules for calculating when proceedings must begin. Always check the specific legislation if your matter falls outside mainstream criminal law.
Either-Way and Indictable Offences: No Statutory Time Limit
For many serious offences, including fraud, sexual offences, serious violence, drug trafficking and murder, there is no equivalent of the 6-month rule. The police investigation time limit in the UK simply does not apply to these categories.
In practice, investigations can run for months or years before a charging decision is made. Prosecutors generally apply the Full Code Test when the Crown Prosecution Service (CPS) makes the charging decision, although the Threshold Test may apply in limited circumstances. Gathering and reviewing the necessary evidence can take time.
Illustrative Investigation Timescales
There is no fixed national timetable for most police investigations. These ranges are illustrative rather than statutory deadlines or national averages.
Why Do Police Investigations Take So Long?
Even where investigators work diligently, several structural factors push timelines out:
Forensic backlogs: These can also contribute to delays, particularly where investigators are waiting for DNA, toxicology or other specialist results. A case may be delayed while investigators await forensic evidence.
CPS review times: Once police complete their file, it must go to CPS lawyers for a charging decision. Complex cases may take weeks or months to progress through the CPS review and charging decision process.
Digital evidence: In modern investigations, examination of phones, laptops, cloud accounts and encrypted messaging apps is routine. Extraction and review of large volumes of messages and other digital material may require considerable specialist resources and time.
Disclosure obligations: The Criminal Procedure and Investigations Act 1996 places obligations on the police and prosecution to identify, retain and review relevant material that may be subject to disclosure. Very large investigations, especially complex frauds, can produce large volumes of material.
Witness availability: In historic cases or cases with multiple complainants, Achieving Best Evidence (ABE) interviews can add significant time to get witness cooperation and scheduling.
Is There a Statute of Limitations in UK Criminal Law?
The short answer is not in the way the term is used in the United States. The phrase 'statute of limitations UK criminal' is commonly searched by people familiar with the American concept, but the UK legal framework works differently.
In the UK, the closest equivalent is narrower: the 6-month rule under s.127 of the Magistrates' Courts Act 1980 applies to most summary-only offences. For many either-way and indictable offences, including fraud, historic sexual abuse and serious drug offences, prosecution can still take place years after the alleged offending, provided the legal requirements for prosecution are met.
There are a small number of exceptions in specific legislation (for example, certain minor regulatory or customs offences carry defined limitation windows), but these are the exception rather than the rule. If you are searching for a statute of limitations that protects you from old allegations, the position is that there is no general limitation period for serious offences. However, specific offences can be subject to statutory exceptions.
What You Can Do About a Slow Police Investigation
Being under investigation for an extended period can be stressful and disruptive. There are some steps to take to possibly influence how long the police have to investigate a crime in the UK. These are the practical options available to you:
Instruct a specialist pre-charge solicitor immediately: A solicitor can write to the officer in the case (OIC), request an update on the timeline, and in appropriate cases seek disclosure of what material has been gathered. Early engagement also gives you the best opportunity to make representations to the CPS before a charging decision is made, a process known as pre-charge engagement.
Make representations to the CPS: If the investigation has reached CPS, your solicitor can write directly to the reviewing lawyer to argue that the evidential test is not met or that prosecution is not in the public interest.
Request a review through the force: If you believe an investigation has been mishandled, your solicitor can consider the appropriate police complaints or review process. Where the concern involves officer misconduct, the Professional Standards Department may be relevant.
Abuse of process application: There are extreme cases where excessive delay has prejudiced your ability to defend yourself (witnesses have died, evidence has been lost, memories have faded). In such scenarios, your solicitor can apply to the court to stay the prosecution as an abuse of process. That is a high threshold, and the court will take into account the length of the delay and whether there has been significant prejudice to the fairness of the proceedings.
Independent Office for Police Conduct (IOPC) complaint: If you have evidence of police misconduct, a complaint may be appropriate. Most complaints are initially handled by the relevant police force. The IOPC deals with the most serious and sensitive matters and can also be the relevant body for certain reviews.
How Bail and Release Under Investigation (RUI) Interact With Investigation Length
Your status during an investigation affects both the constraints on you and the time pressure on police.
Pre-Charge Bail
Following reforms in the Police, Crime, Sentencing and Courts Act 2022 (in force from October 2022), the applicable bail period generally begins with an initial period of 3 months. Further extensions are possible at different levels of authorisation. For standard cases, extensions from 3 to 6 months require Inspector authorisation, and from 6 to 9 months require Superintendent authorisation. Further extensions require magistrates' court authorisation and can be granted where the statutory requirements are met. The applicable time limits concern the period of pre-charge bail and do not impose a general deadline for completing the underlying investigation.
Released Under Investigation (RUI)
RUI mean, you have been released without bail conditions while the investigation continues. Crucially, RUI carries no statutory time limit. There is no fixed deadline by which the police must conclude the investigation or make a charging decision solely because someone has been released under investigation. If you are on RUI and have heard nothing, instructing a solicitor to make proactive contact with the force is one practical step available.
Frequently Asked Questions
Is there a time limit for police to charge you in the UK?
For most summary-only offences, proceedings must generally be commenced within 6 months under s.127 of the Magistrates' Courts Act 1980. For many either-way and indictable offences, there is no equivalent general limitation period, although specific offences can be subject to statutory exceptions.
What is the 6-month rule?
The 6-month rule is the colloquial term for the limitation period under s.127 of the Magistrates' Courts Act 1980. Proceedings not commenced within the statutory period will generally be time-barred.
Can police investigate a crime from years ago?
For many either-way and indictable-only offences, the police can investigate events from many years or even decades ago. Historic sexual abuse prosecutions and old fraud matters are routinely brought before the courts. There is no general statute of limitations for these offences.
How long do most police investigations take?
It varies enormously. A straightforward summary offence may be resolved in weeks. Serious fraud, sexual offences, organised crime and historic abuse cases can take considerably longer, sometimes extending over several years depending on the evidence and complexity. Forensic delays, CPS review times, and the volume of digital evidence can all contribute to extended investigations.
Can I make the police hurry up an investigation?
Not directly, but a specialist solicitor can make formal representations through several routes: writing formally to the officer in the case, engaging with the CPS via pre-charge representations, and requesting a force review. In cases of serious prejudicial delay, they can make an application to the court for a stay as an abuse of process.
Does the UK have a statute of limitations?
Not in the broad American sense. The UK has the summary offence 6-month rule under s.127 MCA 1980, plus some specific limitations in niche regulatory statutes. But there is no general statute of limitations in UK criminal law that protects a suspect from prosecution for a serious offence after a fixed period of time.
Under Investigation? Speak to a Specialist Defence Solicitor Now
If you are the subject of a police investigation, whether you have been arrested, interviewed, placed on bail, or left on RUI, early specialist advice can help you understand your position and make appropriate representations before a charging decision is made. How long the police have to investigate a crime in the UK depends on several of the factors listed above.
At Holborn Adams, we are pre-charge specialists. Our approach is to engage proactively with investigators and the CPS where appropriate, including making representations on the evidence and public interest considerations before a charging decision is made. If charges are brought, we work to build the strongest possible defence from the outset.
Call our team now for a confidential, no-obligation chat about your situation.
