State v. Barbara E. Harp, 2005 WI App 250
For Harp: Aaron N. Halstead, Kathleen Meter Lounsbury, Danielle L. Carne
¶13 The Fifth Amendment to the United States Constitution and article I, section 8 of the Wisconsin Constitution prevent the state from trying a defendant multiple times for the same offense.  “[G]iven the importance of the constitutional protection against double jeopardy, the State bears the burden of demonstrating a ‘manifest necessity’ for any trial ordered over the objection of the defendant.” Seefeldt, 261 Wis. 2d 383, ¶19 (citations omitted). “Manifest necessity” means a “high degree” of necessity. Id.
The trial court’s error was in deeming certain testimony to be in the nature of an “alibi” and thus in violation of the notice-of-alibi requirement; because the testimony was not, as a matter of law, alibi-related, no such violation occurred and the mistrial wasn’t manifestly necessary, ¶¶21-25.