Not sure I'm following you. If they were truly innocent then there would be no forensics or physical evidence that a GJ would buy, so no worries. If there is a lot of evidence, the only way to avert a trial is to taint the jury pool via the media so the DA knows he has no chance. That's the way I see it, anyway.
Now, it could be that they were just REALLY unlucky and a lot of forensics and physical evidence mounted that just didn't jive with reality. THERE I could see the need for a spin machine.