CHAPTER II — GENERAL PRINCIPLES OF CRIMINAL RESPONSIBILITY
PART 6 — CIRCUMSTANCES IN WHICH THERE IS NO CRIMINAL RESPONSIBILITY
Division 4 — Circumstances involving external factors
Intervening conduct or event
39. A person is not criminally responsible for an offence that has a physical element to which absolute liability or strict liability applies if—
(a) the physical element is brought about by another person over whom the person has no control or by a non human act or event over which the person has no control ; and
(b) the person could not reasonably be expected to guard against the bringing about of that physical element.
Other defences - national proceedings
EDIT.