Unlawful act

The unlawful act must be a criminal offence as a civil wrong is not enough (Franklin (1883)). In Lamb (1967), defendant and victim were playing with a revolver, as a joke, defendant pointed gun and pulled the trigger, killing victim. It was found there had been no assault because the victim shared in the joke and so felt no fear of violence. Defendant found not guilty of manslaughter.

An omission cannot not give rise to liability. As Phillimore LJ stated: .. a charge of manslaughter should not be an inevitable consequence, even if the omission is deliberate... (Lowe (1973)).

Dangerous act

The test for dangerous act is an objective one. There is a requirement that a reasonable person would have foreseen the harm, not necessarily the defendant and the risk only needs to be some harm not serious harm (Church (1966)).

It does not matter if the victim was the person the unlawful act was aimed at (Larkin (1943)). As Lord Humphries noted, if a defendant is engaged in an unlawful act towards another and .. quite inadvertently he causes the death of that other person by that act, then he is guilty of manslaughter....

The unlawful act may be aimed at property (Goodfellow (1986)).

However, the risk of harm must be physical an emotional disturbance is insufficient (Dawson (1985)).

If a reasonable person would be aware of the victim’s frailty and increased risk of physical harm the defendant would be liable (Watson (1989)).

Substantial cause of death

Unlawful act must be the substantial cause of death (Corion Auguiste (2004)).

The general rules of causation apply to involuntary manslaughter so the chain of causation must be proved and unbroken. An novus actus interveniens may break chain of causation (Kennedy (2007)).

The unlawful and dangerous act is not required to be the sole cause of death, so long as not a trivial cause (Shohid (2003) Carey (2006)).

A series of unlawful acts may be sufficient (Attorney General’s Reference (no. 4 of 1980)).