DSD & Anor v The Commissioner of Police for the Metropolis

Article 3 of the European Convention on Human Rights imposes a positive duty on the police to investigate credible allegations of torture or inhuman or degrading treatment, including serious violence inflicted by private individuals. The duty is one of means, not results. The investigation must be independent, impartial, prompt and reasonably capable of establishing the facts and identifying and punishing those responsible.

Liability requires more than an isolated error. The court must assess the investigation as a whole, including systemic and operational failures, and apply a fact-sensitive proportionality assessment. An eventual conviction does not necessarily cure earlier serious failures where unreasonable delay has permitted further offending. Article 8 does not provide broader protection in this context.

Two victims of John Worboys, the convicted black-cab rapist, brought claims under sections 7 and 8 of the Human Rights Act 1998 against the Commissioner of Police for the Metropolis. They alleged that the Metropolitan Police Service had failed effectively to investigate their complaints of drug-facilitated sexual assault.

The claims concerned both systemic failures, including inadequate training, supervision, intelligence-sharing and resourcing, and operational failures in the individual investigations. The central issues were whether Article 3 imposed a duty to investigate serious violence by private parties without police complicity, what the content and limits of that duty were, and whether the investigations had breached it.

1. Duty under Article 3. Article 3, read in the light of the Strasbourg authorities and the Human Rights Act 1998, imposes a duty on the police to conduct an effective investigation where there is a credible or arguable allegation that a person has suffered torture or inhuman or degrading treatment. The duty applies even where the violence was inflicted by a private individual and the police were not complicit in it.
2. Content and limits. The investigation must be independent, impartial, subject to scrutiny, prompt and reasonably capable of establishing the facts and identifying and punishing those responsible. It is a duty of means, not a guarantee of a particular result. Not every error or failure to comply with an internal procedure is actionable. The court must examine the investigation in detail and as a whole, allowing the police a margin of appreciation and considering proportionality, resources, the nature of the offence, vulnerability and systemic causes.
3. Period of assessment. In a serial-offender case, the relevant period may begin before the claimant’s own assault, because the duty has preventative and organisational-learning purposes. It may extend through the criminal process. A later conviction can render earlier operational failures irrelevant where it follows within a reasonable time after an adequate investigation, but cannot cure serious earlier failures where delay has enabled further offences.
4. Application to DSD. The MPS failed to train reception and investigating officers adequately, record the taxi driver and witness details, interview a vital witness, obtain relevant CCTV, maintain proper supervision, use intelligence systems and treat the complaint as a serious drug-facilitated sexual assault. Those omissions were individually and cumulatively capable of leading to earlier identification and apprehension. The later prosecution of Worboys did not expunge the breach.
5. Application to NBV. The MPS failed to conduct timely searches under section 18 of the Police and Criminal Evidence Act 1984, preserve and pursue evidence, obtain and analyse the correct CCTV, re-interview Worboys, use intelligence systems and treat the complaint as a serious sexual offence. The failures allowed further assaults and materially delayed effective investigation.
6. Article 8 and relief. Article 8 did not provide broader protection than Article 3 on these facts. The Defendant was liable to both claimants for breach of the Human Rights Act 1998, and each claimant was entitled to a declaration. Quantum was adjourned for later determination.