Two principles laid down in Pipersburg v R (Belize)  UKPC 11 (noted here 26 February 2008 on another point) were applied in Trimmington v R (St Vincent and the Grenadines)  UKPC 25 (22 June 2009). These concern determining when the discretionary death penalty is appropriate for murder.
Lord Carswell, for the Board, summarised the approach (21):
"It can be expressed in two basic principles. The first has been expressed in several different formulations, but they all carry the same message, that the death penalty should be imposed only in cases which on the facts of the offence are the most extreme and exceptional, "the worst of the worst" or "the rarest of the rare". In considering whether a particular case falls into that category, the judge should of course compare it with other murder cases and not with ordinary civilised behaviour. The second principle is that there must be no reasonable prospect of reform of the offender and that the object of punishment could not be achieved by any means other than the ultimate sentence of death. The character of the offender and any other relevant circumstances are to be taken into account in so far as they may operate in his favour by way of mitigation and are not to weigh in the scales against him. Before it imposes a sentence of death the court must be properly satisfied that these two criteria have been fulfilled."
This case was not of "the most extreme and exceptional" kind, so the Board substituted a sentence of imprisonment for life.
It is easy, although a little unfair, to push this to absurdity. The Board did not elaborate on how it compared this case to other murder cases. Did it look at murders internationally, or just murders on Saint Vincent and the Grenadines? Is the local judiciary entitled to apply local values in assessing what is "extreme and exceptional"? Is it necessary to accumulate a body of murders, so to speak, to establish standards against which the latest case can be measured? If murders in a given country are usually carried out in quite savage ways, does that establish a cultural norm?
And, how relevant is post-death mutilation or other indignity carried out by the killer? In Trimmington there was some of this, but the death was caused by throat cutting. On the good side, there was no planning or premeditation, prolonged trauma to or humiliation of the deceased. Those are things that accompany lawful executions.