In criminal law cases are very rarely thrown out on appeal, in murder cases it is almost unheard of, according to Torrance Criminal Attorney  Matthew Ruff.   In a very brief opinion, the US Supreme Court (8-1) reversed a conviction for five counts of first-degree murder because the prosecutor engaged in unscrupulous conduct.   The only evidence of the defendant’s guilt was a single eyewitness, who told the jury the defendant was the guy. 

The D.A. failed to disclose the eyewitness’s two prior statements that he couldn’t see the shooter.  The information was clearly favorable and not disclosed.  So the only issue was materiality.  The Justices said the evidence was indeed important and would likely have resulted in an acquittal (materiality). The Court does an excellent job of explaining why this information was material.  This is over a dissent by Thomas.    Smith v. Cain; 2012  132 S.Ct. 627.