Ylst v. Nunnemaker

In this case we decide whether the unexplained denial of a petition for habeas corpus by a state court lifts a state procedural bar imposed on direct appeal, so that a state prisoner may then have his claim heard on the merits in a federal ha-beas proceeding.

I

In 1975, respondent Nunnemaker was tried in California state court for murder. He raised a defense of diminished capacity and introduced psychiatric testimony in support. In response, the State introduced — without objection from respondent — the testimony of a psychiatrist based upon a custodial interview. The jury found respondent…