Rock v. Arkansas
483 U.S. 44, 107 S.Ct. 2704, 97 L.Ed.2d 37 (1987)

  • Rock got into an argument with her abusive husband.  She called the police, who arrived at the scene to find the husband dead, and Rock holding a gun, completely hysterical.
  • Rock professed that she could not remember what happened.  Her attorney took her to a hypnotist, and under hypnosis, she stated that she was holding the gun, but never actually pulled the trigger.
    • A gun expert was brought in, and he found that the gun was defective and prone to firing when knocked around.
  • At trial, Rock attempted to introduce the hypnotically-derived testimony.
    • The prosecution objected on the grounds that the testimony was inadmissible.
      • The prosecution argued that a defendant's testimony is limited to matters that they can prove were remembered before hypnosis.
  • The Trial Judge excluded the testimony, but allowed the gun expert's analysis into evidence.
    • Arkansas has a State law that excluded hypnotically-derived testimony on the grounds that it was inherently unreliable.
  • The Trial Court convicted Rock of manslaughter.  She appealed.
  • The Arkansas Supreme Court affirmed.  Rock appealed.
    • Rock argued that the limitations on her testimony violated her right to present a defense.  However, the Arkansas Supreme Court found that "the dangers of admitting this kind of testimony far outweigh whatever probative value it may have."
  • The US Supreme Court reversed and remanded for a new trial.
    • The US Supreme Court found that under the 6th Amendment a defendant has a right to testify in their own defense.  The Court found that the Arkansas Supreme Court failed to perform a constitutional analysis.
    • While the US Supreme Court noted that hypnotically-derived testimony is often incorrect, it isn't always incorrect, and so Arkansas' absolute bar to hypnotically-derived testimony was an impermissible and arbitrary violation of the 6th Amendment right to testify in your own defense.
      • The Court noted that in this case, the gun expert's findings corroborated Rock's hypnotically-derived memory, which is a good argument for admissibility.
  • In a dissent, it was argued that an individual's right to represent evidence is always subject to reasonable restrictions and that the right to present evidence is not absolute.  There is a convincing argument that hypnotically-derived testimony is inherently unreliable, and therefore it is reasonable for Arkansas to bar it from admissibility.