What is it?
This is a form of homicide (an unlawful killing) where a person causes the death of another person in circumstances where they were extremely careless and (normally) due to the position that they hold, it is right to hold them criminally liable.
A good definition was set out by the House of Lords in the case of Adomako  UKHL 6. This states that someone will be guilty of gross negligence manslaughter if:
- they owe a duty of care to the deceased,
- which they breached,
- and the breach caused the death, and
- the behaviour was such that it is properly characterised by the jury as criminal
This can be a very complicated one (and the 4th part of the test is pretty circular). In Adomako, Dr Adomako was an anaesthetist who failed to notice that a tube that provided oxygen to a patient during an operation had become disconnected. He was guilty because he owed a duty of care to his patient which he breached by failing to notice that the tube had been disconnected. They jury judged that this was such a clear and serious failing that he should be criminally liable.
It has been said (Boyer, 1981) that gross negligence (and other forms of ‘involuntary’) manslaughter carries the widest possible range of sentences, from a conditional discharge up to a life sentence. There is a very good summary of the issues for sentence in the case of Johnson  EWCA Crim 2976 which is, unfortunately, online. A list of aggravating features are :
- multiple deaths
- a prolonged and deliberately dangerous course of conduct
- an awareness of a significant risk of death or really serious injury
- ignoring warnings that a course of conduct was dangerous or potentially dangerous, and
- pursuing a course of conduct for financial gain
This came from a builder who had been working on a chimney, so all the factors will not always be relevant, but it is worth looking at.