The Supreme Court heard arguments Tuesday in a case testing whether judges may inquire into allegations of racial bias in jury deliberations. The court was divided, though the justices seemed to agree the case before them presented "smoking gun" evidence of racial discrimination.

Legal rules in most states bar judges from hearing testimony about jury deliberations after a trial is over. While the Supreme Court has generally upheld these rules, it has left open whether such juror inquires might be justified in extreme cases.

On Tuesday it heard just such a case, involving the conviction of a Colorado horse trainer for groping two teenage girls. The trial ended in a deadlocked jury, and then a partial verdict on the lesser charges. Afterwards, two of the jurors signed affidavits declaring that another juror, identified in court papers as H.C., had repeatedly expressed a bias against the defendant — and his alibi witness — because they are both Hispanic.

Specifically, the jurors quoted H.C. as saying that, from his experience as an ex-policeman, he knew that the defendant was guilty because "Mexican men ... think they can do whatever they want with women" and that the defendant's alibi witness was not credible because he was "an illegal."

In fact, the witness testified at trial that he was a legal resident of the United States, and that the defendant was with him when the offense took place.

The trial judge, however, refused to allow questioning of the jury because state law bars post-verdict inquiry into whatever happens in a jury room.

Representing the defendant, Stanford Law School Professor Jeffrey Fisher said the ban on post-verdict inquiries into racial bias violates the Constitution's guarantee of a trial by an impartial jury.

Racial stereotypes, standing apart from any other kinds of bias, are "uniquely poisonous" in light of our history and constitutional system, Fisher told the justices.

Chief Justice John Roberts and Justice Samuel Alito attacked that assertion. What makes racial discrimination in jury deliberations any worse than discrimination based on someone's religion, or gender, or sexual orientation, they asked.

Fisher said that this case is about race only, and he noted that the court has previously treated racial discrimination differently from other types of discrimination in the criminal justice system.

"The question is the timing of when somebody has to object," Justice Stephen Breyer observed. And the state's point is that, if we allow objections after the verdict, it will "open the door to all kinds of evils."

Fisher replied that the defense can't object to juror racial bias during deliberations because lawyers aren't in the jury room to hear what goes on. He said that's why some 20 jurisdictions allow inquiry when there is evidence afterward of a jury verdict tainted by race.

Colorado Solicitor General Frederick Yarger defended the Colorado rule against post-verdict inquiry, saying it prevents juror "harassment and tampering" after the trial.

"Suppose this were a capital case," Justice Anthony Kennedy asked. "Would the government ... make this argument, that the person can be executed despite what we know happened in the jury room?"

Yes, replied Yarger, "It ought to apply in that context as well."

"So the more insidious the evil ... the more caution we should have in inquiring of the jury," Kennedy observed caustically.

Chief Justice Roberts saw the issue from a different perspective. If we were to allow a racial bias exception to Colorado's rule, might it not just "alert people" to "keep quiet" about their biases "yet still have the same sort of pernicious effect on the verdict?"

Justice Elena Kagan dismissed that notion. "Now, here, we have screaming race bias in the jury room .... the best smoking-gun evidence you're ever going to see." Although in the past "we've said there need to be special rules to address this prevalent and toxic problem in our criminal justice system," she asked, "here, we're not going to do that?"

Kagan, Kennedy, Justices Sonia Sotomayor, and Ruth Bader Ginsburg, sounded ready to allow post conviction inquiries into racial bias on juries. Justice Breyer sounded a little iffier. But if he joins the other four, that would make for a clear majority in favor of post conviction inquiries into allegations of racial bias in jury deliberations.

If he votes the other way, the court would likely be tied. That would mean the lower court decision upholding the Colorado rule would remain in place, at least until the Supreme Court is ready to tackle the issue again.

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