Often, it consists of evidence improperly withheld by the state that would have been helpful to the defense. The U.S. Supreme Court has ruled that such so-called Brady material is grounds for a new trial. But as direct appeals are essentially limited to the trial record, these collateral issues aren't raised until defendants have lost their direct appeals. It can't be amended no matter what turns up later, and the deadline can't be extended while defense attorneys pursue public records that the authorities may not want to give them. There's the trap.
Investigative files are exempt from disclosure while a direct appeal is pending.
The Supreme Court said so unanimously in a 1990 case that was seen as a defense victory because it said prosecutors couldn't suppress material forever. But with the new law in the picture, defendants wouldn't be able to get the material until it was too late to use it. By then, however, they are ineligible to use it unless they can show the evidence would have convincingly proved them innocent. The highly publicized cases of half-brothers William Riley Jent and Earnest Lee Miller come to mind. Convicted of murdering a woman in Pasco County, they came within 16 hours of electrocution in 1983 before U.S. District Judge George C. Carr granted stays.