Smith v. Cain, 565 U.S. 73, 132 S. Ct. 627 (2012), is a United States Supreme Court decision clarifying the Brady v. Maryland standard for criminal discovery.

"[2] The defendant, Juan Smith, was convicted of murdering five people during an armed robbery based upon the testimony of a single witness.

[3] Smith appealed the verdict because the prosecution failed to disclose statements made by that witness to an investigator prior to trial that the witness:[3] All Louisiana state courts rejected Smith's appeal and the Supreme Court granted certiorari.

"[1] As the Court explained, quoting Kyles v. Whitley, the "reasonable probability" standard looks to whether "the likelihood of a different result is great enough to 'undermine confidence in the outcome of the trial.

'”[3] The Court stated that the witness's statements were "plainly material," because they were the only evidence linking the defendant to the crime.