A federal appeals court reversed itself, ruling Monday that the Army Corps of Engineers is not liable for devastation caused in Hurricane Katrina from a government-built navigation canal.

The Court of Appeals for the Fifth Circuit ruled that the government is immune from lawsuits for decisions made by the corps that might have left the 76-mile channel, the Mississippi River-Gulf Outlet or MR-GO, vulnerable.

“MR-GO’s size and configuration greatly aggravated the storm’s effects on the city and its environs,” wrote Judge Jerry E. Smith, writing for a three-judge panel, adding that the federal tort claims act “completely insulates the government from liability.”

In March, the same panel had ruled that the government was liable for some of the flooding, affirming a landmark ruling by Judge Stanwood Duval Jr. of federal District Court in 2009.