But "due process of law" has already included an arrest based on probable cause, an arraignment before a judge, a grand jury indictment (typically), a judge allowing the trial to move forward and ultimately go to the jury, and a defense attorney challenging the prosecution's case at every step and probably asking for a dismissal, a mistrial and a directed verdict of acquittal. There are certainly bad defenses and unjust convictions, and juries can certainly buy into bad arguments, but there's just no basis for claiming that a jury would unanimously say "We know he didn't do it, but let's send him to prison anyway." When has that happened? The police and the prosecution believe she committed murder, and the judge allowed the charge to stand. That's all part of the due process of law.