Dangerous hypotheticals

One of the common judicial rear-protecting stratagems is to reason in the form "even if I'm wrong, I'm right."

That is, a decision on the basis of particular assumptions would be the same if those assumptions were wrong.

For example, if evidence is ruled admissible on the basis that there was no impropriety in the way it was obtained, a judge may say that even if the alleged impropriety had existed the evidence would still have been excluded.

I criticised that sort of reasoning a while ago: "Shaheed balancing: three propositions" [2004] New Zealand Law Journal 475. So did the Chief Justice last month, when with Blanchard, Tipping and McGrath JJ she delivered the reasons for granting leave to appeal in Hamed v R [2011] NZSC 27 (24 March 2011) at [15]:

"[15] Although the Court of Appeal indicated its view, in application of s 30 of the Evidence Act, that all the evidence should be admitted even if unlawfully obtained or obtained in breach of s 21 of the New Zealand Bill of Rights Act, we have some doubts as to whether it was in a position to express a view on the proportionality of exclusion. An assessment of this kind requires the gravity of the infringement to be carefully balanced against the benefits of admission of the evidence. Since the Court of Appeal took the view that there was no infringement, it was an unnecessary and perhaps artificial exercise for it to undertake the s 30 assessment in respect of the evidence it considered to have been lawfully obtained under s 198 warrants."

The misuse of hypotheticals is quite common. The Supreme Court did it itself in a passage that I have only now noticed: in Condon v R[2006] NZSC 62, an important decision on the status of the right to a fair trial, noted here in August 2006. In its penultimate paragraph the Court says [89]:

"After considering all of these matters, we have not been persuaded that the outcome of the trial would necessarily have been the same if Mr Condon had been legally represented. In our view there was therefore unfairness in the trial and accordingly a substantial miscarriage of justice has occurred."

The trouble here is that the result if there had been no error (ie if legal representation had been obtained), that is, if the trial had been fair, is irrelevant to the question of whether the trial had been fair. If the trial was unfair the conviction had to be quashed, regardless of the strength of the prosecution evidence. If an error at trial caused a real risk that the jury would not be impartial, that would render the trial unfair. A partial jury could nevertheless reach a correct verdict, but it would still be a partial jury delivering a verdict at an unfair trial.

On this point the Court had reasoned better in Sungsuwan v R [2005] NZSC 57, which was noted here in August 2005, and I observed that the majority of the Privy Council in Howse v R (New Zealand) [2005] UKPC 31 had fallaciously asked what course the trial would have taken if the relevant errors had not occurred. The way to avoid this artificial exercise is to ask, given that the errors occurred, what was their effect on the fairness of the trial.

In Sungsuwan the effect of the error on the verdict was a sufficient, but not a necessary, condition for a finding that the trial was unfair. It is one of the ways in which unfairness may be manifest. Another is where partiality existed although the verdict was inevitable. The sufficient condition should not be treated as if it was a necessary condition, as occurred in Matenga v R [2009] NZSC 18 at [31] footnote 39 where the Court defined a substantial miscarriage of justice as one which affects the result of the trial.