William R. Day,
Kepner v. United States — Opinion of the Court
“ Undoubtedly in those jurisdictions where a trial of one accused of crime can only be to a jury, and a verdict of acquittal or conviction must be by a jury, no legal jeopardy can attach until a jury has been called and charged with the deliverance of the accused. But, protection being against a second trial for the same offense, it is obvious that where one has been tried before a competent tribunal having jurisdiction he has been in jeopardy as much as he could have been in those tribunals where a jury is alone competent to convict or acquit. ”
