The three-member appellate panel wasn't ruling on whether the atomic veterans deserve compensation. A 1988 law provides that. To succeed, though, veterans must prove they were present at a radioactive site and that they contracted a radiation-related illness or were exposed to a cancer-causing radiation level.

Required military test records can be elusive. A 1973 fire destroyed many veterans' records, and veterans consider alternative "dose reconstruction" estimates inaccurate.

"You send a Freedom of Information Act request," Broudy said, "and you wait and you wait and you wait, and then maybe you get a piece of it, or you get nothing at all because they say it's classified."

The latest lawsuit sought to force Pentagon officials to release all relevant records. In the opinion written by Appellate Judge Thomas Griffith, appointed by President Bush last year, the court panel agreed unanimously that atomic veterans couldn't compel a massive release of all the Pentagon's relevant documents.

Instead, individual veterans must file individual claims.

If the Pentagon is "covering up records of medical tests that describe the amount of radiation to which these veterans were exposed, FOIA (the Freedom of Information Act) provides a potential remedy," Griffith wrote.

A new study by Melinda Podgor for the Elder Law Journal found that 18,275 atomic veterans had filed for compensation as of October 2004. Only 1,875 claims were granted.

On a separate but related legal track, veterans such as Columbia, S.C., resident John Goricki and Homestead, Fla., resident Richard B. Holmes were pursuing claims following exposure during the Shipboard Hazard and Defense project of the 1950s and 1960s.

Project SHAD allegedly exposed up to 10,000 soldiers and sailors to biological and chemical agents. Like the atomic veterans, SHAD survivors claim that the Pentagon clings to secret information. Like the atomic veterans, they couldn't persuade the appellate court to order the release of all relevant documents.

The veterans "can still seek, through FOIA, the documents they believe they need to pursue their benefits claims," the appellate panel ruled.