Ds either grew and used cannabis so as to alleviate severe pain/sleeplessness or gave it to others who said that they needed it to alleviate pain. They were all convicted, in some cases after the judge refused to allow defence of necessity, and some after the judge had given a different definition to the standard one. Either way, CA said that there was no defence of necessity since for the defence to work there had to be fear of death or serious physical injury: not just pain. LJ Mance said that different principles applied to necessity depending on the area concerned. In R v Z Lord Bingham said the law was merely concerned with a potential excuse. In Re Conjoined Twins LJ Walker said that it was about choosing the lesser of two evils.. LJ Mance says Bingham’s confined definition is a good one. For necessity to apply, there had to be extraneous circumstances capable of scrutiny by judge & jury (i.e. there has to be an “outside” influence- it would not be “necessity where D drove when disqualified to stop her herself committing suicide). For example, in Rodger  1 Cr. App. R. 143, D (a prison warder) allowed X (a prisoner) to escape since X was having suicidal thoughts, necessity was NOT allowed, since the danger was not external and could not be objectively assessed, but instead was internal and therefore subjective. As Bingham said in R v Z there had to be a “just and well grounded fear” of death or serious injury for duress of circumstances/necessity to apply.