Also known as: in the light of reason and experience · FRE 501 · reason and experience
Written by attorneys · grounded in primary & secondary sources — see below
A standard of interpretation directing federal courts to develop common-law privileges by drawing on traditional principles while adapting them to contemporary policy needs and practical realities in federal litigation. The standard supplies the default rule for privilege claims in federal-question cases unless the Constitution, a federal statute, or Supreme Court rules dictate otherwise.
Israel Irving, a professor, sued Innovate Pharmaceuticals in federal court under a federal anti-discrimination statute after his tenure denial. The company withheld confidential peer-review letters, citing a state academic privilege statute. The court evaluated the privilege claim under federal common law because the federal statute supplied the rule of decision.
Imani Idowu, general counsel for Ideal Solutions, directed employees to submit reports on possible regulatory violations. When the government later sought those reports, the company asserted attorney-client privilege. The court applied federal common-law principles developed in light of reason and experience to decide which employees qualified as clients.
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Ivy Ibarra moved to suppress recordings that state officers had seized in violation of the Fourth Amendment and later turned over to federal prosecutors. The government argued the evidence should be admitted because the federal agents had not participated in the seizure. The court assessed the exclusionary rule by reference to federal common-law principles shaped in light of reason and experience.
Ian Iverson was charged with drug trafficking after a confidential informant tipped off officers. At trial the defense demanded the informant’s name. The government resisted disclosure. The court decided whether to recognize a privilege by applying federal common law interpreted in light of reason and experience.
Ingrid Innes sought discovery of attorney-client communications between Integrity Partners and its counsel. She alleged the communications furthered an ongoing fraud. The court examined the documents in camera to determine whether the crime-fraud exception applied under federal common-law standards developed in light of reason and experience.
Irene Ingalls was subpoenaed to testify against her husband in a federal criminal prosecution. She invoked a privilege against adverse spousal testimony. The court decided the scope of the privilege by reference to federal common law interpreted in light of reason and experience rather than a fixed historical rule.
Federal common law governs when a federal statute or other federal law supplies the rule of decision for the claim or defense to which the evidence relates. State privilege law applies only in civil cases where state law supplies the rule of decision.
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Courts weigh the policy interests served by confidentiality against the need for evidence, guided by traditional common-law principles and practical experience in federal litigation.
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No. The court looks to the source of the rule of decision for the particular claim or defense to which the evidence relates. Federal privilege principles still control evidence bearing on federal claims even when supplemental state claims are present.
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…by the Court of Appeals in this case cannot, consistent with "the principles of the common law as . . . interpreted. . . in the light of reason and experience," Fed. Rule Evid. 501, govern the development of the law in this area. III Our decision that the communications by Upjohn employees to counsel are covered by the attorney-client…