The more interesting question isn't for the jury-- for whom the race of a defendant has long been swamped by other evidence-- but for a police officer deciding whether or not a person's suspicious behavior is sufficient reason to stop and question them. Not only does including race in that assessment seem rational but it is something police officers almost certainly do (if not consciously) which makes it rather more interesting as a policy question.

Pinker is not distinguishing between members of the audience and members of the jury. For the audience, Pinker is basically correct. The prior probability that the defendant committed the acts charged is fairly high, given the evidence available to the audience that the government charged the defendant with a crime. But the jury is given an instruction by the judge that the defendant is entitled to a presumption of innocence that must be overcome by the government. In Bayesian terms the judge means, "For social reasons not directly related to evidence, set your prior probability that the defendant is guilty as close to zero as is logically possible for you. If the probability of guilt is sufficiently high after hearing all the evidence, then you may vote to convict." If a rationalist juror ignores this instruction and acts like a rational audience member, then the juror is doing wrong, as Pinker notes. But ignoring the judge's instruction is wrong, and Pinker is not presenting a great insight by essentially highlighting this point.