5th amendment: double jeopardy
1. When jeopardy attaches: at empaneling and swearing of jury in a jury trial or swearing in of first witness in a bench trial
2. Exceptions permitting retrial: hung jury; trial discontinued due to manifest necessity or at behest of A on ground other than acquittal on merits; A’s successful appeal of conviction; A’s breach of plea bargain
3. Same offense: if crime requires an additional element the other does not, then not same offense; lesser included offenses count as the same; exception: new evidence such as victim later dies
4. Separate sovereign rule: separate sovereigns may try A for same offense if each have jurisdiction; local gov’t not separate from state