The brother of one of two men abducted and killed in 1964 says he was shocked by a U.S. federal appeal court's decision to overturn last year's conviction of a purported Ku Klux Klan member, but he will pursue the decades-old case.

James Ford Seale is escorted to a federal courthouse in August 2007. (Rogelio V. Solis/Associated Press)James Ford Seale has spent the past year and a half behind bars after he was sentenced to three life terms in June 2007 for kidnapping and conspiracy in the abductions of Charles Eddie Moore and Henry Hezekiah Dee.

The two 19-year-olds disappeared on May 2, 1964, while hitchhiking in southwestern Mississippi at the height of the civil rights movement. Their mangled, decomposed bodies were found more than two months later in the Mississippi River.

The cold case was revived when David Ridgen, a CBC documentary maker, and one of the victim's brothers, Thomas Moore, tracked down Seale — long believed dead.

On Tuesday, a three-judge panel of the 5th U.S. Circuit Court of Appeals agreed with Seale's lawyer that the statute of limitations in the case had expired.

"The more than 40-year delay clearly exceeded the limitations period," the 20-page ruling written by Judge Harold DeMoss said.

'Haven't been knocked down'

Moore admitted that he was initially shocked by the ruling but has decided to continue fighting to keep Seale behind bars.

Charles Moore, left, and Henry Dee, in a school yearbook photo, were killed in 1964. (Handout photos)"I haven't been knocked down," Moore told CBCNews.ca in a phone interview Wednesday from his home in Colorado Springs, Colo. "And as long as I'm alive I'll pursue charges against James Ford Seale."

Federal prosecutors have 21 days to appeal the decision, said Ridgen, who also seemed hopeful that another conviction is possible.

"The three white judges were very clear in their written decision that they overturned the Seale conviction because of a statute of limitations technicality rather than the facts of the case," Ridgen wrote in an e-mail to CBC News.

He notes that a mixed 12-person jury convicted Seale last year.

"Now his community knows the facts. And the world knows them. The truth has come out where it never would have before," he said.

When charges were laid against Seale last January, U.S. Attorney General Alberto Gonzales said Seale had not been charged with murder because prosecutors deemed it too difficult to prove.

But Moore said they are working to charge Seale with murder. Ridgen noted there is no statute of limitations on murder charges at state level in Mississippi.

Thanks to recent media attention on the cold case, Moore said he has been flooded with offers of help from legal experts, lawyers and others. "We're going to pull it together," he said.

Victims dumped alive into river

CBC's Ridgen tracked down the victim's brother in 2005 in Colorado, then persuaded him to accompany Ridgen on trips to Mississippi to revisit his brother's murder.

Seale's family had been telling reporters for years that Seale had died. But in July 2005, Moore and Ridgen found Seale living near the site of the kidnapping.

The prosecution's star witness was a confessed Klansman, Charles Marcus Edwards, who testified he and Seale belonged to the same chapter.

Back in 1964, Seale, then 28, and Edwards, then 31, were arrested in the original investigation. They were later released on a bond and no trial was held.

Federal prosecutors said the case was dropped because local law enforcement officers at the time were in collusion with the Klan.

Edwards was granted immunity for testifying at the trial. He said the two victims were stuffed into the trunk of Seale's Volkswagen and driven to a farm. He testified Seale told him Dee and Moore were attached to weights and dumped alive into the river.

Seale has been serving his sentences at a federal prison in Terre Haute, Ind., where he was sent so his health needs could be met, officials have said. He has cancer, bone spurs and other health problems.

With files from the Associated Press