AAD, AAH and AAI provides important guidance for those defending child victims of trafficking

In R v AAD, AAH, and AAI [2022] EWCA Crim 106, the Court of Appeal Criminal Division has overturned DS [2020] EWCA Crim 285; [2021] 1 WLR 303 and ruled that the abuse of process jurisdiction is open to victims of trafficking seeking to argue that they ought not to be prosecuted on that basis. The jurisdiction is available before trial or as a route to appeal after conviction.

The Court upheld the decision in R v Brecani [2021] EWCA Crim 731 that a conclusive grounds decision is not admissible in a criminal trial, but provided guidance on the sort of matters that a suitably qualified expert in trafficking can address instead.

It has also importantly summarised guidance on when a guilty plea entered, including by a victim of trafficking, may be overturned.

The decision will be important for many children in criminal proceedings. Children are especially vulnerable to trafficking and to exploitation as victims of modern slavery. The guidance will be relevant to many children and young adults who have faced exploitation in “county lines” drugs supply cases, as well as to those who have been trafficked to the UK from other countries.

This article considers four aspects of the criminal process that may be useful in the defence of a (child) victim of trafficking following AAD, AAH, and AAI: (1) sending written representations to the CPS; (2) using the abuse of process jurisdiction; (3) adducing expert evidence at trial; and (4) overturning a guilty plea.

For a fuller commentary on the judgement by the same authors, see this article.


1. Written representations to the CPS

Since DS and Brecani, practitioners may have faced increased resistance from the CPS when making representations that they should discontinue a prosecution because an accused is a victim of trafficking or modern slavery on the basis of a positive conclusive grounds decision. AAD will be an important decision in assisting any such representations, as it confirms there are avenues through which a conclusive grounds decision can be admissible, and, if not, that a suitably qualified expert can give evidence.

Representations should address whether the abuse of process jurisdiction would be available should the CPS continue the prosecution or refuse to agree admissions about the defendant being a victim of trafficking, and whether a suitably qualified expert would be instructed at trial.

2.  The abuse of process jurisdiction

The Court confirmed that the abuse of process jurisdiction is still available to victims of trafficking issued with a Conclusive Grounds decision [¶¶ 110-143].

The jurisdiction provides a route to stay a trial that is unjust. It is available in cases where (i) it will be impossible for the accused to receive a fair trial, or (ii) it would be unjust to try the accused. Where the CPS ought not to have prosecuted the accused, a victim of trafficking can appeal against a conviction that resulted from the prosecution.

The jurisdiction is available at any point in the trial process, including in an appeal against conviction.

The existence of the jurisdiction is crucial in ensuring that the CPS complies with its duty of non-prosecution of victims of trafficking. However, after DS it appeared that the jurisdiction was not available where it was argued that the CPS ought not to prosecute an accused who had received a positive conclusive grounds decision. In that case, the Court of Appeal held that deciding the facts relevant to the status of an individual as a victim of trafficking is solely and “unquestionably” a matter for the jury [¶ 40], ordering that proceedings which had been stayed as an abuse of process in the Crown Court following a positive conclusive grounds decision be continued.

In AAD, AAH and AAI, the Court confirmed that the CPS can prosecute a victim of trafficking despite a positive conclusive grounds decision. But it clarified at ¶120 that:

“…what if the CPS has failed unjustifiably to take into account the CPS Guidance or what if it has no rational basis for departing from a favourable conclusive grounds decision?  […] in principle such a scenario would, on ordinary public law grounds, seem to operate to vitiate that prosecution decision: whether by reason of a failure to take a material matter (viz. the CPS prosecution guidance) into account or by making a decision to prosecute which is properly to be styled as irrational.  Consequently, such a prosecution may, in an appropriate case, be stayed.”

The Court accepted that DS has been superseded by VCL & AN, App. Nos 77587 and 74603/12, 16 February 2021. In the latter case, the ECtHR stated that the prosecution of victims of trafficking “may be at odds with the state’s duty to take operational measures to protect them” [¶ 159]. As such, a prosecutor must have “clear reasons which are consistent with the definition of trafficking contained in the Palermo Protocol and the Anti-Trafficking Convention” to depart from a decision by the competent authority [¶ 162].

This led the Court of Appeal to reject the observations in DS [¶ 42] that if there is no sound evidential (rational) basis on which to challenge the conclusive grounds decision, then “it will still not be an abuse of process, but the judge will consider any submission that there is no case to answer”. That, the Court of Appeal in AAD said, is clearly wrong, and the abuse of process jurisdiction should be available as legal redress in the event that the CPS fails to follow their own guidance [¶ 140].

3.  Expert evidence for victims of trafficking at trial

The Court upheld Brecani and confirmed that a conclusive grounds decision would not be admissible at trial.

The Court confirmed that a suitably qualified expert can be instructed to give evidence to the jury on matters which are outside of its knowledge or remit. By way of example, it stated that evidence of “the defendant’s psychiatric or psychological state or the detailed mores of people trafficking gangs operating in countries that are outside the court’s own knowledge and experience” would be admissible [¶87]. However, it stressed that where an expert’s evidence strays into questions of fact for the jury to decide, it is inadmissible [¶86]. Examples given are the plausibility and consistency of a defendant’s account, the vulnerability of a defendant, and whether a given set of facts meets the legal definition of trafficking [¶86].

Although the decision does not deal with county lines, it would be open for the practitioner to argue, although the court may not accept, that the nature of county lines smuggling in the UK is outside the knowledge of the jury.

4.  Overturning a guilty plea

The Court cited the guidance from a recent case, R v Tredget [2022] EWCA Crim 108, which identified three general, non-exhaustive categories of case where a Court may overturn a guilty plea [¶¶ 155-157]. Though it did not provide specific commentary for victims of trafficking, the guidance provides a useful reference point for practitioners. The three categories are (I) where the defendant was deprived of a defence in law; (2) where it was unjust to try the defendant at all; and (3) where the defendant’s guilty plea was false and they did not commit the crime at all.

Practitioners should be aware of the defence available under s 45 of the Modern Slavery Act 2015 which applies to those who have been compelled to commit an offence due to being trafficked or enslaved, relevant to the first category of case

The Court allowed the appeal of AAH, who had received a positive Conclusive Grounds decision after entering a guilty plea.

Research published by the University of Exeter in 2021 indicates that children are more likely to plead guilty when incentivised to do so, for example through the availability of credit for an early guilty plea or of a referral order. This clarification may therefore be particularly significant for children.


AAD, AAH, and AAI will prove useful for practitioners working with children and young people who are victims of trafficking. An overarching theme of the judgement that will be important to navigate in future cases is when questions of fact should be left to the jury, and when an NRM referral is relevant or an expert can be instructed. Practitioners working with children exploited via county lines should take care to make clear why the realities of trafficking in the UK are outside the knowledge of the jury, so that a suitably qualified expert can be instructed to assist the case.



Written by

Margo Munro Kerr and Sarah-Jane Ewart, Barrister, One Pump Court