Let us suppose that a judge in a criminal trial were to say as follows: "Statistics show that young men are more likely to be involved in a traffic accident than other demographic groups. Therefore I conclude that the young man before me is guilty of the charge of reckless driving." Or suppose the judge were to say, "in my observation, based on many years on the bench, prostitutes tend to be unreliable witnesses. Therefore we can discount the testimony of the complainant, a prostitute who claims she was raped." Or suppose the judge drew the same sorts of broad generalizations, fair or unfair, about other groups -- natives, immigrants, women -- and what is more, used these to decide particular cases.

Would we say that the judge was "properly contextualizing" the case at hand? Would we accept his "life experience" as a licence to label whole sections of the population as untrustworthy or prone to crime? At a minimum, would we accept these stereotypes in place of any evidence that the tendencies alleged of the group were also present in the individual before the court?

To ask the question is to answer it. If the characteristics of the group were all, if sociology were destiny, we would have no need of a trial, the purpose of which is to prove that this individual committed this crime -- not that individuals like him are known to commit crimes like it. All the same, judges being human, we should not be surprised to find such biases creeping into the odd lower court ruling. What is more surprising, what is frankly scandalous, is that the justices of the Supreme Court, by a margin of 6 to 3, should now have sanctioned this basic error of reasoning as accepted jurisprudence.

The court heard of a case in Nova Scotia involving a black youth and a white police officer. The youth was accused of assaulting the officer in a bid to prevent the arrest of another boy. As it turned out, the case pitted one party's word against the other's; which of the two widely conflicting accounts was true is not at issue here. What is remarkable is the judge's reasons for deciding against the officer, and acquitting the youth. I repeat them here, a little masterpiece of rhetoric masked as reasoning, supposition in place of fact, dissembling over plain speaking.

"I'm not saying that the Constable has misled the court," she began, "although police officers have been known to do that in the past. I am not saying that the officer overreacted, but certainly police officers do overreact, particularly when they're dealing with non-white groups." "That" -- what "that": that he was a police officer? -- "to me indicates a state of mind right there that is questionable. I believe that probably the situation in this particular case is the case of a young police officer who overreacted.

And I do accept the evidence of [the youth] that he was told to shut up or he would be under arrest. That seems to be in keeping with the prevalent attitude of the day." And then this final, bizarre flourish: "At any rate, based upon my comments and based upon all the evidence before the court, I have no other choice but to acquit." As evidence supporting her decision, the judge cites her own comments, the content of which was that since police officers in general tend to be liars, the constable must also be lying. But then, she had no choice but to quote herself, since no other evidence was presented before the court that would impugn the credibility of the witness.

Yet the majority of the Supreme Court upheld the verdict. A minority within the majority fretted that the judges' remarks "came very close to the line," at least to giving the appearance of bias against the police officer. But the rest would not even go so far as this mild rebuke. Her remarks, they wrote, "were not unfortunate, unnecessary, or close to the line." Rather, "in alerting herself to the racial dynamic in the case, she was simply engaging in the process of contextualized judging." Again, the issue here is not whether police officers are, on the whole, racists, or indeed whether society is: the issue is whether these broad generalizations about groups can be applied, without corroborating evidence, to particular individuals. It argues neither for nor against the judge's reasoning in this regard to note that she was herself black, and might be expected to know a thing or two about racism from her own life experience. As the Court's minority wrote in its dissent, life experience "is an important ingredient in the ability to understand human behaviour, to weigh the evidence, and to determine credibility. It helps in making a myriad of decisions arising during the course of most trials. It is of no value, however, in reaching conclusions for which there is no evidence." "The fact that on some other occasions police officers have lied or overreacted is irrelevant. Life experience is not a substitute for evidence."