Federal judges do not lightly overturn convictions to punish prosecutorial misconduct. But especially unusual was U.S. District Judge Kurt Engelhardt’s September 17 order granting five former New Orleans police officers a new trial after sentencing them for their roles in the Danziger Bridge shootings and cover-up following Hurricane Katrina.

Any judge, even if he or she wants to teach federal prosecutors a lesson, would hesitate in a case of such public significance, in which a retrial would distress victims, burden witnesses, prolong proceedings and undermine public confidence in the fairness and integrity of criminal justice.