R v Slingsby [1995] Crim LR 570

Facts

• Simon Slingsby engaged in consensual sexual acts with the victim.
• During these acts, Slingsby wore a signet ring that inadvertently caused small internal cuts to the victim’s vaginal walls.
• The cuts became infected, leading to septicaemia and, after a short period, to the victim’s death.
• Slingsby was charged with manslaughter on the basis that the injuries, though unintended, resulted from a criminal act.
• No allegation of assault, battery, or reckless infliction of harm was advanced apart from the sexual activity itself.

Issues

1. Whether accidental harm resulting in death, caused during consensual sexual acts, constitutes unlawful act manslaughter.
2. Whether the victim’s consent can operate as a defence when the injury was neither intended nor foreseen.
3. Whether the original agreed act violated criminal law, thereby supplying the unlawful act necessary for a manslaughter conviction.
4. Whether the statutory and common-law requirements that the act in question be both unlawful and objectively dangerous were satisfied in the circumstances.

Decision

• The Court of Appeal quashed Slingsby’s conviction and entered an acquittal.
• It held that the sexual acts themselves were lawful because they were fully consensual and involved no deliberate or reckless infliction of harm.
• The injuries were an unforeseen accident; the presence of the ring was not intended to produce pain or bodily harm.
• As no assault or battery could be identified, there was no “unlawful act” on which to build a manslaughter charge.
• Because the central element of unlawful act manslaughter—the commission of a separate offence—was absent, the conviction could not stand.
• The Court emphasised that criminal responsibility should not be imposed merely because the eventual outcome was tragic.

Legal Principles

• Unlawful act manslaughter requires: (a) a completed criminal act, (b) that the act be objectively dangerous, and (c) that it cause death.
• Consent can remove the unlawfulness of conduct that would otherwise amount to assault or battery, provided the conduct is not itself prohibited (as sadomasochistic injuries were in R v Brown [1994] 1 AC 212).
• Where parties engage in ordinary, mutually desired sexual activity, the law presumes the activity is lawful unless it crosses established limits of bodily harm.
• A defendant is not liable for manslaughter if the fatal injury arose purely by accident during a lawful act, even though the physical consequence was unforeseen and severe.
• The decision reaffirms that liability for unlawful act manslaughter cannot be based on a lawful act that unexpectedly produces harm; there must be a distinct offence, such as assault, present from the outset.
• The Court distinguished cases involving deliberate infliction of injury—where consent is no defence—from accidental injury cases, illustrating that the policy concerns addressed in Brown do not extend to unforeseen wounds arising from ordinary consensual intercourse.
• The ruling illustrates the boundary between criminal and civil liability: while negligence might give rise to a civil claim, criminal punishment requires proof of an unlawful and dangerous act or gross negligence.

Conclusion

R v Slingsby confirms that consensual, lawful sexual activity does not transform into a criminal act simply because unforeseeable injuries prove fatal. For unlawful act manslaughter, the prosecution must show a pre-existing crime, such as assault, along with objective danger. In the absence of an unlawful act—and where the defendant neither intended nor foresaw harm—the presence of consent defeats criminal liability. The case therefore clarifies that accidents during lawful intimacy, however tragic, fall outside the scope of manslaughter unless an independent offence is first established.