This decision-making framework provides police with an innovative tool that they can use to decide whether it is ethically appropriate to investigate cases of non-recent child sexual abuse.

We spoke with Colin Paine, Thames Valley Police Detective Chief Superintendent, about the new CSE framework developed with Dr Hannah Maslen, deputy director of the Oxford Uehiro Centre for Practical Ethics. The framework is a new and innovative guide with which the police can decide whether it is ethically appropriate to investigate cases of non-recent child sexual abuse.

Focus on non-recent child sexual abuse

Child Sexual Abuse (CSA) is the forcing or enticing of a child or young person to take part in sexual activities. Child Sexual Exploitation (CSE) is a subcategory of CSA and occurs where a child is persuaded, coerced, or forced into sexual activity in exchange for, amongst other things, money, drugs/alcohol, gifts, affection or status.

As Hannah (lead author) and Colin point out in their article published in the Thames Valley Police journal and open access in the Journal of Criminal Justice Ethics, the police service has seen a consistent increase in the number of reports of non-recent CSA. Non-recent in this case is defined as the abuse ending at least one year prior to it being reported to the police. The establishment of Operations Yewtree and Hydrant are high-profile examples of investigations into non-recent CSA.

The ethical dilemma of non-recent CSE

Non-recent CSE can leave investigators with difficult ethical decisions as, commonly, it is a third party rather than the victim(s) who reported it to the police. Where the victim has not come forward, it can be challenging for investigators to determine whether an investigation would harm them psychologically through the act of ‘cold calling’ and speaking to them. Further the cost of investigating in such non-recent cases is very high not only in terms of money, but time and opportunity cost too; for example, the article identifies that on average complex CSE cases can take 9 investigators 2 years to complete at an average cost of £885k – the equivalent of 268 rape investigations.

However, the gravity of CSE and the potential threat of the suspected offender harming more victims are factors that weigh heavily in favour of investigation. There is therefore a need for a comprehensive framework that can guide investigators through making the complex decision to either investigate or not.

The current guidance used by the police in England and Wales is the National Decision Model (NDM).  However, Colin and Hannah suggest this model is not ‘intended to address the intricacies of specific strategic decisions’. Furthermore, they note that other guidance mechanisms tend to detail ‘how investigations should be conducted, but not advise how to determine whether they should be conducted’.

Important considerations in cases of non-recent CSE

To design their framework, Colin and Hannah first identified and analysed the considerations that factor into determining whether a complaint of non-recent CSE should be investigated or not:

  • Considerations relating to the victim: These include respect for victims’ wishes and privacy. A victim could be vulnerable to psychological and social harms due to the investigation. Victims’ well-being also needs to be taken into account, particularly because an investigation can bring about ‘secondary victimisation, i.e. the investigation could exacerbate the trauma of the initial assault and lead to further harm to the victim such as self-harm, family breakdown or even suicide attempts.
  • Considerations relating to the purposes of policing - crime prevention and criminal justice: Protecting citizens by preventing crime is a central purpose of the police service, and an investigation that convicts and punishes offenders who would have re-offended fulfils this. This purpose is also served by deterring other potential offenders. The other central purpose of the police is to serve justice. Through conviction, justice is served and the state shows the offender’s crimes are unacceptable and deplorable.
  • Considerations relating to limited resources: In the current climate of austerity and reduction in police numbers, it is important for the police service to “ration” investigations, there must therefore be consideration of the opportunity cost of investigating complex CSE cases which tend to be resource intense. Analysis within Thames Valley Police alone shows that the average complex CSE case has 7 victims, 88 witnesses, 21 suspects and ultimately 10 defendants, with costs of more than £800,000. As Hannah and Colin note, in such cases, if it is possible that ‘significantly more of the relevant goods of policing can be achieved were the resources directed elsewhere’, then there is a reason not to direct resources to the CSE investigation.
  • Considerations of procedure and police accountability: Police officers are held to high standards of accountability such that the fear of complaints, and potential for dismissal, can skew the decision-making of police officers and investigators. They might be incentivised to arrive not at the right decision, but at the decision with the lowest risk of personal liability.
The Oxford CSA Framework

The framework designed by Hannah and Colin is mainly based on the considerations above. The framework provides ‘principled guidance’ on the relative importance of these considerations and their significance in a particular case. It argues for an overlapping hierarchy of considerations that focuses on two things:

  1. The inherent moral significance of the considerations; and
  2. How much weight we should accord the reasons these considerations generate, given uncertainty regarding outcomes.

Using these two factors, the framework argues that the most significant consideration when deciding to investigate a non-recent CSE offence is harm prevention. This is due to the fact that the primary purpose of the police is to protect people’s rights such as the right to bodily integrity, one that is egregiously violated in instances of CSE. The second most significant consideration is the victim’s wellbeing, specifically the ‘rights-like’ interests they have in mental and social stability. The third is the context of limited resources, and the trade-offs that pursuing investigation would involve. Societal considerations are ranked fourth because any compromise to public support is less tangible than the harms at stake in other considerations. Procedural considerations and accountability carry no weight in deciding whether to investigate but do in ‘how decisions are made and justified’.

The framework uses ‘a numerical approach to structure the weighing up of reasons of differing strength, with room for discretion and required justification’. In making the final decision, the framework guides investigators to weigh up the relevant considerations and to recognise that some considerations will be traded off against another. This practical approach ‘supports a move away from the decision-making being a form of artistry within policing, towards a more ethically nuanced and robust decision-making process’. The fact that this framework makes it possible for the considerations’ weight to change based on the given case means that the most justified decision can be made using this framework.

Further, the approach to generating a framework could be used as a model for decision-making within policing beyond the investigation of non-recent CSA to include other challenging decisions that involve weighing, or trading off, competing considerations.

The framework is currently being used in a large case where it is expected to save Thames Valley Police a significant amount of resources. Those using the framework on this case have attested to its efficiency and effectiveness with a lead investigator calling it “the Horlicks framework” because it helps him sleep better at night.

For more information about the Oxford CSA framework, contact the lead author of the project Dr Hannah Maslen via and Detective Chief Superintendent Colin Paine via


This case-study was compiled and edited by Michael Farinu in 2019

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