But the trial has already been taking place in this case. The jury's been seated, and arguments and testimony have begun. *If* the prohibition against double jeopardy applies, jeopardy would be attached already. That's how it works in a guilt trial at least.
But Double Jeopardy would not seem applicable here.
DOUBLE JEOPARDY - Being tried twice for the same offense; prohibited by the 5th Amendment to the U.S. Constitution. '[T]he Double Jeopardy Clause protects against three distinct abuses: [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.' U.S. v. Halper, 490 U.S. 435, 440 (1989).
(lectlaw.com)