Causation
In result crimes the prosecution must prove that the defendant's conduct both factually and legally caused the prohibited consequence. Legal causation asks whether the defendant's act was a substantial and operating cause.
What "Causation" covers
- Factual causation uses the 'but for' test: but for the defendant's act, would the result have occurred (White)?
- Legal causation requires the act to be a substantial (more than minimal) and operating cause; it need not be the sole cause.
- Take your victim as you find them — the thin skull rule covers physical and psychiatric conditions and religious beliefs (Blaue).
- A free, deliberate and informed act of a third party or the victim may break the chain of causation (novus actus interveniens).
- Medical treatment breaks the chain only if it is so independent and potent that the original wound is merely part of the history (Jordan; Smith; Cheshire).
- Victim's escape/self-neglect breaks the chain only if the response was not reasonably foreseeable (Roberts; Williams).
- Supplying drugs which the victim freely self-injects generally breaks the chain (Kennedy (No 2)).
Key cases & statutes
The authorities and provisions most likely to matter for this subtopic:
How it's tested in SQE1
SQE1 uses single best answer questions: a short factual scenario, one precise question, and five options of which only one is the best answer on the law applied to the facts. For causation, expect to be asked what the correct legal position is, what a party may or must do, or which outcome follows — with more than one option looking arguable. Reading the facts carefully and eliminating the near-misses is the skill that earns the mark.
Where candidates lose marks
- Treating any medical mistake as breaking the chain — only wholly independent, potent treatment does (Cheshire sets a high bar).
- Applying only factual causation — 'but for' alone is not enough; legal causation must also be established.
- Overlooking that the victim's own foreseeable reaction (e.g. jumping from a car) does not break the chain.
Learn this subtopic in the course
A video lesson, notes and exam-style practice on causation.
FAQ
Is causation tested on SQE1?
Yes — causation is part of the SQE1 Criminal Liability syllabus (FLK2) and can appear in single best answer questions.
How is causation examined in SQE1?
SQE1 tests it by application: you're given a realistic scenario and choose the single best answer from five options. The focus is on using the law correctly, not reciting it — knowing the leading authorities (R v White, R v Blaue) helps.