"If a legal rule requires a fact to be proved (a 'fact in issue') a judge or jury must decide whether or not it happened. There is no room for a finding that it might not have happened. The law operates a binary system in which the only values are zero and one. The fact either happened or it did not. If the tribunal is left in doubt, the doubt is resolved by a rule that one party or the other carries the burden of proof. If the party who bears the burden of proof fails to discharge it, a value of zero is returned and the fact is treated as not having happened. If he does discharge it, a value of one is returned and the fact is treated as having happened."
“ … the FTT lost sight of the fact that after establishing whether the PLN was validly issued, the evidential burden in relation to the assessment to VAT on [the company involved] shifted to [the taxpayer challenging the PLN] when he sought to positively challenge the assessment as the sole basis on which the PLN was invalidly issued”