What constitutes double jeopardy?

Double jeopardy involves a provision of the Fifth Amendment to the US Constitution that says a person may not be tried twice for the same offense. For a detailed discussion of the double jeopardy...

yes

As a matter of constitutional law, at the federal level the 5th Amendment to the US Constitution. At the State level, the 14th Amendment due process clause that "passes through" the 5th Amendment...

It protects the accused from being arrested and tried over and over again on the same identical offense.

It means you can't be tried twice for the same crime: for example, once in a state court and then again in a federal one.