DSD and the Article 3 investigative duty: the long road to justice

Monday 26 February 2018

Stephen Clark, a member of our Civil Liberties and Human Rights team, discusses the recent Supreme Court judgment in DSD & NBV v. Commissioner of Police for the Metropolis [2018] UKSC 11.

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The investigative duty

It is sometimes said that the European Convention on Human Rights (‘ECHR’) contains two types of duty for the State to comply with: negative and positive obligations. The negative obligation is to refrain from violating the right themselves. In the case of Article 3, this means ensuring that state agents and bodies do not engage in torture or the infliction of inhuman and degrading treatment on individuals in the UK’s jurisdiction. The positive obligations are a collection of different duties for the State to take positive steps to protect those rights. This ranges from making sure there is an effective legal framework in place to taking action if they know there is a real and immediate risk that those rights are going to be breached.

The investigative duty is a species of positive obligation that requires the State authorities to carry out an “effective” investigation into complaints of human rights abuses. The majority of the case law relates to its application under Article 2 – the right to life – but a series of Strasbourg authorities have extended it to Articles 3 and 4 more recently (see OOO v. Commissioner of Police for the Metropolis and Rantsev v. Cyprus and Russia).

DSD is the first domestic case to deal with its scope and application.

The Facts

DSD & NBV are two of the victims of John Worboys, the taxi driver who perpetrated over 100 assaults and rapes on women. Both of them had made early reports to the police of being attacked by Worboys in 2003 and 2007 respectively, but were failed by the following investigation into their complaints. Rather than carrying out an effective investigation into the allegations against Worboys, the Metropolitan Police failed at both a systemic and an operational level to investigate DSD and NBV’s claims. Their failures ranged from a fundamental failure to provide adequate resources and training to officers to specific operational failures such as failing to interview key eye witnesses and gather CCTV.

As a consequence of the Metropolitan Police’s failings, Worboys was able to continue attacking women until he was finally encountered and arrested in 2008. For DSD, this came some five years after she had originally been assaulted by Worboys.

Barred from pursuing a negligence claim against the police as a result of the judgment in Hill (on which, see Garden Court’s blog on the recent Supreme Court decision in Robinson), DSD & NBV pursued a Human Rights Act claim against the Metropolitan Police – arguing that it had violated Article 3 of the ECHR by failing to carry out an effective investigation into their allegations against Worboys.

The decisions under appeal

Their cases were heard in the High Court in 2014, in front of Green J. The High Court found that the Metropolitan Police had failed to carry out an effective investigation into their allegations against Worboys – awarding DSD and NBV in damages the sums of £22,250 and £19,000 respectively. The Commissioner for the Metropolitan Police was aggrieved by the judgment and sought to appeal the decision to the Court of Appeal, arguing, inter alia, that: there was no investigative duty under Article 3; that any such duty was only triggered by state complicity in the Article 3 ill-treatment; and, in any event, Article 3 had not been breached by the Metropolitan Police. Lord Justice Laws, giving the lead judgment, dismissed the grounds of appeal.

The Supreme Court

The Commissioner continued to be aggrieved and pursued her arguments in the Supreme Court. In a judgment handed down on 21st February 2018, the Supreme Court unanimously dismissed the appeal – but disagreeing in their reasons why. Lord Kerr gave the leading judgment, which Lady Hale and Lord Neuberger agreed with. Lord Kerr found that Article 3 created an investigative duty on the state authorities – breach of which could involve both systemic and operational failings. The submissions by the Commissioner that the obligations under human rights law should be read down to match the duties under the common law or that the Supreme Court should dismiss the appeal so that Strasbourg could decide this case were dismissed. There was a clear and consistent line of authority from Strasbourg on the nature and scope of the investigatory duty and there was no good reason for the Supreme Court to depart from it.

Lord Hughes disagreed on the question of what investigatory failings would lead to a violation of Article 3. In his view, the compelling reasons of public policy that grounded the common law jurisprudence warranted an approach which meant that only systemic failings could amount to a violation of Article 3. Lord Hughes was hesitant in reaching even that conclusion – he described the creation of both the positive obligations under the ECHR and their application to non-state actors as “glosses” on the text of the Convention which would require revisiting for exhaustive treatment in the future.

Lord Mance gave a concurrence which broadly agreed with everyone, with some caveats.


After a protracted legal battle, DSD & NBV’s case is a significant victory for victims of crime seeking to hold the police – and other public bodies – to account for serious investigatory failures. As can be seen from even the truncated summary above, the Supreme Court’s judgment has a significant amount in it that needs unpacking and raises interesting questions for the future. Not all of them can be addressed here – particularly those touching on the relationship between Strasbourg and domestic courts.

The most significant part of the judgment is in its rejection of the Commissioner’s argument that (1) the investigative duty was limited to alleged mistreatment by state actors or where there was state complicity in the actions of non-state actors and (2) a violation of the investigative duty could only be founded if there were systemic failings at the policy and structural level.

The Justices were right to do so. Although both limbs of the argument were framed in terms of established case law and policy concerns about onerous obligations, they would, if accepted, have had a significant impact well beyond the context of police actions. In truth, they were an attack on principles which have been repeatedly reiterated over 20 years of case law from the Strasbourg court.

If the argument that the Article 3 investigative duty was limited to state actors only was accepted, entire lines of Article 2 and 3 authority would have to be revisited. Although Lord Mance’s judgment suggests that the Article 2 investigative duty is only triggered by an arguable breach of a substantive obligation by a state body, which wrongly conflates the threshold for triggering a Middleton verdict with the investigative duty. To have an effective investigatory mechanism, the Article 2 obligation applies to any death in the jurisdiction, but can be discharged by a combination of a short-form verdict/ “traditional” inquest and access to the courts. In the medical healthcare context, access to the civil courts and a regulator are sufficient to discharge the investigative duty in a “simple” negligence case – whether the clinicians concerned are public or private (see Powell v. UK, Tarariyeva v. Russia, Dodov v. Bulgaria and Tyrell v. HM Senior Coroner for Durham). The same point can be made about the Soering line of cases – where no distinction is drawn between a real risk of Article 3 harm between state and non-state actors (see HLR v. France (1998) 26 E.H.R.R. 29) for the purposes of deportation and removal.

The second limb of the argument does not fare any better. It wrongly tries to conflate the investigative duty with the framework obligation, despite the case law – particularly in the Article 2 context – having repeatedly examined the actual operational steps that took place and judged their adequacy. Although it does not feature in the judgment, comparisons can be drawn with the Strasbourg Court’s approach to the investigative duty in Rantsev v. Cyprus & Russia and the adequacy of the Cypriot police’s investigation into a suspicious death involving a suspected case of human trafficking.

In reality, the Commissioner’s appeal was grounded in pure policy arguments. Some of the commentary on DSD has already taken on a “opening of the floodgates” tone, with the suggestion that police forces will be paralysed by burdensome legal duties and the public purse drained by contentious litigation.

Those apocalyptic visions are hysterical exaggerations. If we go back to the original judgment of Green J in 2014, he makes it abundantly clear the significant number of hurdles a claim has to go through in order to succeed – see [211] to [225] for a summary of those principles. Claimant lawyers reviewing their files in light of DSD should be cautious in advising their clients. While the Commissioner may have lost on the broad question of whether a duty exists, we can expect Defendant lawyers to tenaciously take every possible point in establishing a breach. In particular, they will likely focus on two particular questions:

Was the investigative duty triggered at all?

In order for the duty to carry out an effective investigation to be triggered at all, there needs to be a “credible” or “arguable” claim of Article 3 ill treatment. There will be scope – especially if the “trigger” consists of an uncorroborated  complaint – to attack the victim’s character and credibility, such that the Defendant’s police officers were entitled to disregard the complaint. Early evidence gathering to demonstrate the corroborating evidence before the police will be crucial to combatting this argument.

Does the harm amount to “inhuman and degrading treatment”?

While Lord Hughes suggests that a very broad range of violent and sexual crimes will fall within the ambit of Article 3, this represents a significant opportunity for Defendant lawyers to seek to minimise the reach of the investigative duty. Emphasising the “serious” and “grave” treatment required to meet the Article 3 threshold, they will try to keep the class of cases (whether on a case-by-case or category of offence basis) which can rely on the investigative duty as small as possible. Care needs to be taken in selecting cases to bring, as well as in gathering evidence from the victim. Bringing a number of borderline cases may lead to adverse judgments from the High Court and Court of Appeal which, while obviously they will be decided on their own facts, will detrimentally impact the entire class of cases. If the cases are genuinely borderline, then they need to be very carefully and closely argued from first principles.

This decision represents a real success after a long and hard fought battle in the courts. What follows next, however, will be just as important as what has gone before. There is a substantial amount left to deal with and the next series of judgments on the Article 3 investigative duty may be just as important as this first, ground-breaking one.

Post Script

Since doing the first draft of this piece, commentators from the Defendant side of actions against the police have said that Lord Kerr underestimates the tenacity of Claimant lawyers in bringing cases and pushing at the margins of the case law. It is reassuring that Claimant and Defendant lawyers are, while divided on many things, united on at least one thing – the tenacity of their opposition.

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