This question is out there for all you lawyers (but anyone else is welcome to chime in)…
Consider this scenario:
Harry Hitman is charged with murder (a crime with no statute of limitations in most states). The main evidence is the testimony of Ernie Eyewitness, who was present when the crime was committed. However, before trial, Ernie Eyewitness disappears and is presumed dead. With their case essentially gone, the state drops the charges against Harry Hitman.
Fast forward twenty years.
Ernie Eyewitness comes back (he was in hiding for fear of his life). For whatever reason, he’s now willing to testify.
My question is this: Is a person “in jeopardy” as soon as he’s charged (and can now no longer be charged); or is the defendant “in jeopardy” only once the trial starts (in which case, the DA can start proceedings against Harry Hitman)?