U.S. v. Thomas, No. 11-30120 (6-29-12)(Bea with Gould and Bybee).

The magistrate found that police could detect an odor of marijuana 450 feet or so away, through filtration systems and other smells. This led to the denial of a Franks motion. The district court shook its head at the police's credibility, reversed the magistrate's findings and recommendations, and suppressed. It did so without a de novo or any evidentiary hearing. The government appealed, arguing that the district court had to conduct a de novo hearing when it reversed a magistrate's credibility determinations in favor of the government. After all, a defendant would get a de novo hearing in an appeal from a magistrate's findings. The 9th did not hold that the government had to have a de novo hearing on reversed credibility findings, but it came pretty close. A hearing had to be held so long as the testimony was material and made a difference. If the testimony did not make a difference to the legal ruling, then a hearing was not necessary. The 9th stated that it strongly encouraged and expected that hearings would be held except in limited legal conclusions. As the 9th wrote in vacating and remanding: "We disagree with both of those categorical options, and today we adopt a middle ground, though our rule counsels strongly in favor of holding a de novo hearing. We agree with the defendants that the government does not have an unqualified right to a de novo evidentiary hearing whenever a district judge reverses a magistrate judge’s credibility determinations in a way adverse to the government. But we also agree with the government that its interest in the integrity and accuracy of judicial proceedings—which, after all, similarly underlie a defendant’s due process rights to such a de novo hearing— will often counsel in favor of such a hearing. Thus, we hold that a district court abuses its discretion when it reverses a magistrate judge’s credibility determinations, made after receiving live testimony and favorable to the government, without viewing key demeanor evidence, with one exception: where the district judge finds that the magistrate judge’s credibility determinations had no legally sufficient evidentiary basis, so that, were they jury determinations, judgment as a matter of law would issue for the defendant."