He has a right to a timely trial. Demand it. If the DA isn't ready, too bad. Move for a directed verdict also.
Possibly ask to move the trial out of Austin to a Republican County and then go for a directed verdict.
And when the trial formally begins, the `discovery process’ kicks in, and skeletons will be skedaddling out of many closets. Lots of flattering photos, too.
Perry to his enemies: “Bring it, you stupid jerks.”