In such cases, the defendant must have the mens rea for the relevant crime when he does each of the acts that could constitute the actus reus. An example of this was seen in the case of AG's Ref (No 4 of 1980) [1981] 1 WLR 705. D pushed V down some stairs. He then pulled V back up the stairs by using rope tied around her neck. He also cut her throat. It was unclear whether she had died from strangulation or the stabbing. The court said that it was unnecessary to prove which act caused the death:

'... if an accused kills another by one or other of two or more different acts each of which, if it caused the death, is a sufficient act to establish manslaughter, is it necessary in order to found a conviction to prove which act caused the death? The answer to that question is no, it is not necessary to found a conviction to prove which act caused the death.'