State v. Koennecke, 274 Or. 169, 545 P.2d 127 (1976). [State has affirmative duty to disclose to accused, without any request by him, any evidence which is clearly favorable to accused and material to his guilt or innocence, such as a statement by a third person admitting the crime for which accused is charged. In case in which question whether evidence demanded is favorable to accused and material to his guilt or punishment can only be determined by scientific tests, accused cannot be required to support his motion for discovery by factual showing, by affidavit or otherwise, sufficient to demonstrate that the evidence requested by him is favorable and material.]
Hanson v. Cupp, 5 Or. App. 312, 484 P.2d 847 (1971). [Post conviction relief proceeding. Held: evidence sustained finding that evidence, in hands of prosecution but not disclosed by it to defense, as to information volunteered by several people to the police and to deputy district attorney which, if true and accurate, would have exonerated the petitioner was of such character that failure to turn it over to defense was violation of due process.]
Brady v. Maryland, 373 U.S. 83 (1963). [Suppression by the prosecution of evidence favorable to an accused upon request violates due process where the evidence is material either to guilt or to punishment, irrespective of the good faith or bad faith of the prosecutors.]