Autrefois acquit

For the doctrine of autrefois acquit to apply, it was necessary that the accused should have been put in peril of conviction for the same offence as that with which he was then charged. The word “offence” embraced both the facts which constituted the crime and the legal characteristics which made it an offence. For the doctrine to apply, it would have to be the same offence both in fact and law, or offences which were substantially the same. Legal characteristics were precise things and were either the same or not. Autrefois acquit should be kept within limits that were precise.

There was a public interest in the finality of litigation and in a defendant not being vexed twice in the same matter; but that whether an action was an abuse of process as offending against the public interests involved all the facts of the case, the crucial question being whether the claimant was in all the circumstances misusing or abusing the process of the court. The court required parties to litigation to bring forward their whole case, and would not permit the same parties to open the same subject of litigation in subsequent proceedings which were not brought forward in the first proceedings only because they had, from negligence, inadvertence or even accident, omitted part of their case.