The quality of police recorded crime statistics for England and Wales

The police recorded crime statistics for England and Wales, published quarterly by the Office for National Statistics (ONS), are a measure of the number of crimes reported to and recorded by the police in England and Wales. The Home Office collates recorded crime data from the 43 territorial police forces in England and Wales and the British Transport Police and supplies these data to ONS.

The police recorded crime statistics for England and Wales are published as official statistics, not accredited official statistics. We removed their National Statistics accreditation in 2014 following an assessment which found evidence that the quality and consistency of the underlying data may not be reliable.

This review is the first step towards the statistics being considered for reaccreditation. Accreditation demonstrates that the public can have confidence in the quality of the statistics.

This review looks in depth at the quality of the underlying data used to produce the police recorded crime statistics for England and Wales. It covers the data process from beginning to end – from how police forces record crime, to how data quality is managed and assured by all those involved in their collection and processing, to the production of the final statistics. We identified the key factors that have led to improvements to crime recording by police forces in recent years, and what we see as the main barriers and challenges to ensuring the quality of police recorded crime data.

The police recorded crime statistics are one of two key sets of statistics on crime in England and Wales. The other source is the Crime Survey for England and Wales (CSEW), a household survey of individuals’ experience of crime.

Understanding and interpreting crime statistics for England and Wales is complex. Both data sources have their individual strengths and limitations. The CSEW statistics are the best source for understanding long-term crime trends across England and Wales in crime covered by the survey. For many crime types, the police recorded crime statistics are a better indicator of police activity than trends in crime itself, but they do provide better insight than the CSEW on some higher-harm but less-common crimes like homicide and knife crime. The police recorded crime statistics also cover a broader range of crimes than the CSEW and are available at the police force area level.

Crime statistics are a priority area for us. Our work on police recorded crime statistics is part of a wider programme of regulatory work on crime statistics for England and Wales. Currently, the CSEW statistics are published as official statistics, not accredited official statistics, due to challenges with response rates that affect the quality of the estimates. We will be reviewing the accreditation status of the CSEW statistics in 2024.

This review did not examine the quality of police recorded fraud and computer misuse data, as the process for recording these crime types is different from other crime types. We will review this subset of police recorded crime statistics separately as part of a wider review of the quality and value of fraud and computer misuse statistics for England and Wales later in 2024.

What we found

We gathered evidence across the following stakeholder groups and carried out extensive desk research to support the findings from our engagement. This engagement effort included:

Police forces have made significant improvements to crime recording, but there are common challenges to ensuring the quality of recorded crime data

We identified several common themes and features of good crime recording by police forces. We also gained insight into the barriers and challenges to recording crime accurately and consistently. Our findings may not be generalisable to all police forces, as they are based on a sample of nine police forces, but we think that they give a good indication of what is working well. This review has given us greater confidence in the quality of the underlying recorded crime data overall.

Police forces are recording crime more accurately now than in 2014

HMICFRS has carried out regular inspections of the ‘crime data integrity’ of each police force in England and Wales since 2014. Crime recording accuracy is one aspect of crime data integrity and is a measure of whether the crimes reported to the police are recorded when they should be.

HMICFRS’s inspections estimate that crime recording accuracy nationally has improved in the last ten years , from 80.5% ( ± 2.0% ) of all crimes (excluding fraud) in 2014 to 92. 4 % ( ± 0.3% ) at the end of the 2021 to 20 22 inspection programme, a statistically significant change. Most police forces inspected by HMICFRS in its 2021 to 2022 inspection programme (17 out of 23 forces) were found to record c rime with an accuracy of over 90% (Figure ES1) , although , over time, individual police forces have improved their crime recording accuracy to varying extents .

Given this variation in crime data integrity between forces and over time, HMICFRS has said that it will continue to inspect forces to ensure standards are maintained. HMICFRS plays a vital role in holding forces to account for their crime recording standards, and we consider it is essential that it continues to carry out regular audits of crime data integrity.

The nine police forces that we spoke to confirmed that HMICFRS inspections of crime data integrity had been instrumental in bringing about improvements to their crime recording standards.

We found that there has been a positive shift in the culture around crime recording in police forces since 2014. Now, forces appear to take crime data integrity very seriously and are more committed to ensuring that they meet the national standards of crime recording.

Key features of good crime recording that we identified include strong data leadership and governance, and investment in people, processes and systems. Clear data governance arrangements, regular training and guidance for police officers and staff on crime recording, and centralisation of crime recording by a dedicated crime management unit all support accurate and consistent recorded crime data. For instance, crime data standards or crime data integrity boards enable oversight and scrutiny of changes to the Counting Rules and data quality issues; and police forces with crime management units have greater control over data quality than police forces that rely on frontline officers to enter data.

There are common challenges to ensuring the quality of recorded crime data

We identified some common challenges to further improving crime recording and the quality of recorded crime data, in particular to achieve consistency of data across police forces. These challenges can be attributed to the complexity of police crime recording in England and Wales – there are 44 police forces that potentially manage their crime recording in different ways. The quality of police recorded crime data is influenced by many factors, including the decisions made by police officers and staff when recording a crime; changes to the Home Office guidance on when a crime should be recorded; the different systems and versions of IT systems used to record crime; and the extent of quality assurance applied to the data.

There remain differences in the interpretation of the Home Office Counting Rules (which set out when and how a crime should be recorded), both within and across police forces. Differences in the interpretation of the Counting Rules can vary by crime type and are often due to a lack of understanding of the offence, for example, of domestic abuse offences. To improve understanding of the Counting Rules and recording of specific crime types police forces have rolled out training. Knowledge sharing between police forces through the national and regional crime registrar groups is helping ensure consistency in the application of the Counting Rules across police forces.

The Counting Rules are regularly reviewed and updated. In 2023, they underwent a major review. This led to some changes, including the reversal of a change made in 2017 that required two crimes to be recorded where harassment, stalking or controlling or coercive behaviour was one of the crimes. As a result, there is a now single principal crime rule all offences, except for modern slavery offences and passport application fraud. We found that these changes have been well received by police forces; they are seen as sensible and long overdue. We also identified some concerns about the impact of these changes on data quality, for example, on the understanding of offending patterns of domestic abuse.

Changes to the Counting Rules are an inevitable aspect of crime recording in England and Wales. The Home Office updates the rules to ensure that they remain relevant and fit for purpose. However, one consequence of regular changes to the Counting Rules is that it makes it difficult to determine whether a change in the number of crimes recorded by the police is genuine or whether it is due to a change in crime recording practices. This makes it more challenging for police forces to monitor changes in performance over time and complicates explaining trends in police recorded crime statistics, which reduces the value of the data and statistics for all users. ONS and the Home Office should continue to work together to monitor and explain the impact of the Counting Rules changes on the statistics to users.

Several stakeholders that we spoke to, including some police forces and HMICFRS, explained that the pressure to secure a positive outcome in inspections has led some police forces to adopt an approach of ‘better record a crime in case HMICFRS fails us’. This risk-averse behaviour can lead to over-recording of crime. Strict adherence to the Counting Rules can make a force crime registrar reluctant to authorise the cancellation of crimes, and this can also lead to over-recording of crime. HMICFRS told us that it estimates that several forces are currently over-recording crime in some way.

We found that variation in the IT systems used to record crime by police forces in England and Wales is a barrier to standardising crime recording practices and improving data quality across police forces. There are currently seven different crime recording IT systems in use across police forces in England and Wales, with some police forces running different versions of the system. Each system has specific data issues and challenges, and police forces regularly change systems, which can have a negative impact on data quality and sending data to the Home Office.

Some forces have control over their own data systems and can make changes to their crime recording IT system relatively quickly, whereas other forces rely on external suppliers to make the changes for them, which can take longer and be costlier. One way in which forces are minimising this risk is working together to manage the IT supplier. However, we found that the sharing of knowledge about crime recording IT systems between forces could be improved. Greater knowledge sharing would promote more-consistent and more-efficient use of crime recording IT systems.

We are not confident that the Home Office understands the strengths and limitations of the different crime recording IT systems used by police forces in England and Wales, or how variation in these systems may be impacting the quality of police recorded crime data. To strengthen its oversight of police force data quality, the Home Office should work with police forces to gain this understanding.

While we did not review in depth the quality assurance process for recorded crime data of each force that we spoke to, we found that the stages they applied were broadly similar. Police forces are carrying out internal audits of recorded crime in a consistent way and to a high standard, in line with the Home Office’s Data Quality Assurance Manual, which sets out a minimum standard framework.

However, the standard of quality assurance that is applied when checking and validating crime records is more variable across police forces. The quality assurance arrangements in individual forces are usually shaped by operational priorities and resourcing. Differences in the crime recording IT system may also influence the level of quality assurance that is applied. To support the consistency of quality assurance arrangements across police forces, we encourage police forces to improve knowledge sharing on quality assurance, to learn from each other and promote best practice.

An increasing number of police forces, including a couple of forces that we spoke to, have introduced ‘robotic process automation’ tools as part of their quality assurance process to enhance recorded crime data quality. We welcome the use of these automated tools as they can enhance the level of quality assurance that is applied while reducing the burden on police staff, but there is a risk that forces become too reliant on automated tools and fail to identify and address the root causes of the data quality issues.

The Home Office’s quality assurance processes are well established, but it should strengthen its oversight of police force data quality

The Home Office’s quality assurance processes have been strengthened with the creation of the Home Office Data Hub, a case-level policing and crime database. Almost all police forces now submit record-level data to the Home Office via the Data Hub, which allows the Home Office to carry out more-thorough quality assurance and analysis of the data compared with aggregate data. The police forces that we spoke to were positive about the quarterly ‘data reconciliation’ process, where the Home Office asks forces to verify aggregate statistics for their force which have been derived from their Data Hub returns.

However, we found that the Home Office has a limited understanding of how police forces quality assure their own data. The Home Office told us it expects police forces to quality assure their own data, but it does not monitor the nature or extent of quality assurance applied. The Home Office, as the organisation that collates and supplies data to ONS, is responsible for understanding how police forces manage the quality of their recorded crime data. This includes forces’ quality assurance arrangements.

We expect the Home Office analytical team to work with police forces to build its knowledge of police forces’ quality assurance arrangements. Once the Home Office has gained a good understanding of police forces’ quality assurance arrangements, it should develop a plan for how it will support greater consistency of quality assurance across police forces. To support this work, the Home Office analytical team should consult the National Police Chiefs’ Council (NPCC), which is working to introduce more-standard approaches to data quality.

The Home Office needs to engage with the Quality Assurance of Administrative Data (QAAD) framework, our regulatory standard for the quality assurance of administrative data. We see applying the QAAD framework as essential to the Home Office enhancing oversight of the quality of the police recorded crime data.

The Home Office’s quality assurance processes cannot check whether police forces have recorded the right crime. This requires an audit of crime records, and only HMICFRS performs this function. Therefore, the Home Office and ONS are reliant on HMICFRS for monitoring and reporting crime recording accuracy. For most police forces, the inspection reports are the only source of information about crime recording accuracy, and HMICFRS and the Home Office do not know how accurately police forces are recording crime in between inspections. The Home Office, HMICFRS and ONS should work together and use all available data to develop the most complete and up-to-date picture of crime recording accuracy in police forces.

The Home Office has established a National Data Quality Improvement Service (NDQIS) to improve the quality and comparability of ‘flagged data collections’ such as knife crime, domestic abuse and online crime. The computer-assisted classification tool developed for knife crime has increased the accuracy and consistency of the data between police forces, and similar tools have been rolled out, or are being developed, for other flagged collections. To inform users about the programme and its impact on the quality of the police recorded crime statistics, ONS should publish and regularly update information about current and future NDQIS developments. In addition, ONS needs to better document the methods used and the limitations of the tools.

ONS publishes clear information on quality, but it relies on the Home Office to quality assure data

ONS is two steps removed from the police force data and relies on the Home Office to collate and quality assure the recorded crime data from police forces. Because ONS does not have access to the record-level data, the quality assurance it applies to the data is limited to consistency checks. ONS told us receives more information on quality from the Home Office than it used to, and that communications with the Home Office have improved substantially since the Home Office Data Hub was established. To strengthen its oversight of data quality, ONS should work together more closely with the Home Office and share more knowledge about data quality.

As the statistics producer, it is ONS’s responsibility to publish information on the quality of the police recorded crime data. ONS’s user guide to crime statistics contains clear and detailed information about many aspects of the police recorded crime statistics, and it is updated annually. However, there are gaps in the quality information. In particular, ONS does not provide sufficient assurance for users about police forces’ quality assurance arrangements and the strengths and limitations of different crime recording IT systems used by police forces. In addition, ONS needs to explain the specific changes that police forces have made to improve their crime recording standards. ONS should communicate these aspects of the police force data quality to users, to give them a full picture of quality.

The data quality framework that ONS has developed provides an open assessment of the quality of the police recorded crime statistics and informs users about the quality of the different crime types. ONS needs to be better explain the criteria it uses to determine the reliability of the statistics to enhance the value of this information.

ONS evaluates the consistency and comparability of police recorded crime statistics with other crime statistics, including the CSEW statistics. Comparisons between the police recorded crime statistics and CSEW statistics can reveal disparities in trends in both data sources and data quality issues. A comparative analysis carried out in 2023 identified a divergence between police recorded crime statistics and CSEW statistics. The reasons for the divergence are unclear, and ONS is currently carrying out further work on this. ONS should work closely with HMICFRS, the Home Office and, where necessary, police forces, to establish the drivers of the divergence between the police recorded crime statistics and CSEW statistics.

A framework for quality improvements

Our recommendations for improving the quality of the police recorded crime data and statistics for England and Wales are what we deem as critical to address before we undertake a reassessment of compliance with the Code of Practice for Statistics. Our recommendations cover three improvement areas.

ONS and the Home Office should develop an action plan that sets out how they are going to address these recommendations.

This should be published by early 2025.

1. The Home Office needs to strengthen its oversight of police force data quality.

We consider that insufficient oversight by the Home Office poses a significant risk to the quality of the statistics. The Home Office must understand how police forces manage the quality of their recorded crime data and assure itself of the quality of the data collected by forces.

2. ONS needs to better communicate the quality of the statistics and data quality improvement initiatives to users.

ONS should provide greater assurance for users of the statistics about all aspects of the quality of police force data.