sister Megan Rice
Sister Megan Rice was not a threat to national security with her Bible quotes and banners, the court ruled Facebook

Long-time American peacenik Sister Megan Rice, 85, and two cohorts are not guilty of sabotage for splattering paint and blood on the walls of a US storage facility holding weapons-grade uranium, an appeals court has ruled.

The court did, however, uphold a far lesser charge of injuring government property.

The trio in 2012 cut through several fences at the Y-2 National Security Complex in Oak Ridge, Tennessee, to get to the main uranium bunker. Once there, they hung banners, splashed blood on the walls, painted quotes from the Bible such as "swords into plowshares," sang and prayed and waited to be arrested.

The 6th US District Court of Appeals ruled in a 2-1 decision that the actions did not threaten national security and did not merit charges of sabotage, reports CBS News.

"If a defendant blew up a building used to manufacture components for nuclear weapons the government surely could demonstrate an adverse effect on the nation's ability to attack or defend," the court rules. "But vague platitudes about a facility's 'crucial role in the national defence' are not enough to convict a defendant of sabotage."

Rice has been serving a sentence of just under three years. Her fellow protesters, 66-year-old Michael Walli and 59-year-old Greg Boertje-Obed, have each been serving five years.

Rice has been serving her time in "deplorable prison conditions" in the Metropolitan Detention Center in New York City, the New York Daily News reported early this year. She's being held in a gymnasium-size dorm unit with 60 bunk beds just feet apart for 111 women. Six half-enclosed toilet stalls, six sinks and six shower stalls line one wall. In the middle are 10 tables where they eat. There is no outdoor area and no mess hall.

Defence lawyer Bill Quigley said he hopes the three will be re-sentenced to time already served, and freed.