offense which may be punished by death

When an accused is charged, as here, with transporting a kidnapping victim across state lines, he is charged and will be tried for an offense which may be punished by death. Although the imposition of that penalty will depend on whether sufficient proof of harm is introduced during the trial, that circumstance does not alter the fact that the offense itself is one which may be punished by death and thus must be prosecuted by indictment.

Defined by the Supreme Court in - Smith v. United States, 360 U.S. 1 (1959).