Answer to Question 1
Double jeopardy is a protection afforded under the Fifth Amendment and prohibits the trying of an individual more than once for the same crime. It was designed to limit prosecutorial abuse by the government if the individual was previously tried and acquitted on a matter. Double jeopardy is attached once the jury is sworn in or once a witness is called in a nonjury case. The double jeopardy clause of the Fifth Amendment includes three essential protections for American citizens against: (1) a second prosecution for the same offense after acquittal; (2) a second prosecution for the same offense after conviction; and (3) multiple punishments for the same offense. Individuals may not be tried again for the same crime even in cases in which new evidence conclusively proves their guilt. One exception occurs when a case does not achieve legal finality or conclusion. In most cases, a mistrial falls into this category. Another major exception falls under the separate sovereign concept, in which individuals can be tried for the same offense in two separate jurisdictions. For example a person can be tried at the state and federal level for the same crime or at the state level and have a civil court proceeding for the same crime.
Answer to Question 2
a