An appeals court ruling this week dealt a potentially fatal blow to the bid by federal prosecutors to restore the convictions of five New Orleans police officers in the fatal Danziger Bridge shootings.

Even though it seems likely that the civil rights case will be retried more than a decade after the shooting, the U.S. Justice Department has two remaining avenues of appeal, both of which legal experts liken to a Hail Mary pass.

Aside from taking the issue to the U.S. Supreme Court, the government could request a hearing before the full 5th U.S. Circuit Court of Appeals in New Orleans, based on the fact that one member of a three-judge panel wrote in a dissenting opinion Tuesday that — despite shocking prosecutorial misconduct — the police officers should not have been granted a new trial.

U.S. Attorney Kenneth Polite Jr. — whose predecessor, Jim Letten, left office amid a scandal that erupted around the case — said Wednesday that prosecutors are still weighing their options.

“There have been no decisions made yet,” Polite said. “We are just in the beginning stages of coordinating with (the Department of Justice) to decide what our next step will be.”

Six years after the storm, in 2011, a federal jury in New Orleans convicted former Sgts. Kenneth Bowen and Robert Gisevius and former Officers Robert Faulcon and Anthony Villavaso of opening fire on six unarmed people on the bridge and then orchestrating a cover-up.

The Sept. 4, 2005, shooting claimed the lives of 17-year-old James Brissette and 40-year-old Ronald Madison while injuring four others.

Jurors also convicted the officers of scheming with a fifth defendant, former Sgt. Arthur “Archie” Kaufman, in an attempt to frame one of the victims for firing upon police.

Two years ago, U.S. District Judge Kurt Engelhardt tossed out the officers’ convictions after it emerged that federal prosecutors had been posting anonymous and often acerbic comments under news accounts of the Danziger proceedings on nola.com. The judge threw out the verdicts even without a showing that jurors had been influenced by — or even seen — the online rantings.

In a 2-1 decision this week, 5th Circuit Judges Edith Jones and Edith Brown Clement upheld Engelhardt’s ruling as legally sound, finding that “prosecutorial misconduct commenced even before indictments were handed down and continued throughout the trial and into the post-trial proceedings.” In his dissent, Circuit Judge Edward Prado wrote that even though federal prosecutors “acted deplorably,” the NOPD officers failed to show they’d been deprived of a fair trial.

The Justice Department’s best chance to avoid a costly and complicated retrial would be to persuade the 5th Circuit to hold what’s known as an en banc hearing, several legal observers said.

Such a proceeding is rare and would require a majority of the appellate court’s 15 active judges to essentially agree the case is “so much more important than others that they want to spend their time on it,” said David Coale, a Dallas lawyer who has practiced extensively before the 5th Circuit.

Judges on the court also may request a full hearing themselves, even without a motion from one of the parties. Still, the full court takes up just “a handful” of cases a year, Coale said, and a number of pressing matters are competing for the judges’ attention, including death penalty cases from three states.

“You can have cases that are extremely important in their own right but are so unusual that they’re not attractive for en banc review because the issues aren’t likely to come up again,” Coale said. “But if the government comes back all guns blazing here, they’re certainly going to get listened to.”

The online comments, the bulk of which were authored by former Assistant U.S. Attorney Sal Perricone, have been invoked repeatedly in New Orleans federal court as a parade of defendants have sought — largely unsuccessfully — to have their indictments dismissed in light of the misconduct.

Last month, a separate 5th Circuit panel ruled unanimously that Perricone’s commenting did not justify a new trial for Gregory McRae, a former New Orleans police officer convicted of igniting a car containing the body of a man fatally shot by police during the aftermath of Katrina.

On Sept. 1, yet another 5th Circuit panel will hear oral arguments in the case of Renee Gill Pratt, a former New Orleans city councilwoman and state legislator convicted of racketeering. Her attorney, Mike Fawer, contended in a recent court filing that Perricone “engaged in a sprawling campaign over the course of two-and-a-half years to build a community of bloggers that collectively would influence public opinion.”

If not persuaded by the online commenting issue, the appeals court could decide to have a fuller look at Danziger due to the high-profile nature of the case, particularly considering the movement that has swept the country in the wake of several well-publicized police shootings.

The Justice Department has invested heavily in the Danziger case, holding up the officers’ convictions as just punishment for rampant police misconduct in the wake of Hurricane Katrina.

“It’s hard to think of a case that represents a more extreme case of civil rights abuses than Danziger,” said Ronnie Greene, an investigative journalist who has written a book, “Shots on the Bridge,” chronicling the saga. “These were just good families trying to survive the hurricane. Now here we are 10 years later, and the victims still do not have legal closure.”

The split on the Danziger panel — among three judges appointed by Republican presidents — combined with the somewhat contradictory ruling in the McRae case could be enough to trigger a full hearing before the 5th Circuit, said Sidney Powell, a former federal prosecutor who wrote a book about corruption within the Justice Department.

“They don’t want a decision that’s this excoriating on the books, so it wouldn’t surprise me at all for them try to get rid of it,” Powell said, referring to the prosecution.

“The government is in abject denial as to the breadth, depth and effect of its prosecutorial misconduct nationwide, and it’s an issue that desperately needs to be addressed.”

Staff writer Gordon Russell contributed to this report. Follow Jim Mustian on Twitter, @JimMustian.