Where a mistrial is declared because of “legal necessity,” the double jeopardy clauses of the state and federal Constitutions do not bar a second trial for the same offense. Therefore, where the public defender declared a conflict on the eve of trial after the jury had been selected, and a 120 day continuance was required to allow alternate counsel to prepare, the mistrial was legally necessary because the jury had already been sworn and it would have caused extremely difficult problems to recall the jury 120 days later. Because appellant had the ability to pay his $5,200. restitution fine during the term of his imprisonment, it was not excessive under the federal and state Constitutions. The Legislature may reduce the conduct credits for a murder sentence without voter approval. Therefore, the Legislature’s addition of Penal Code section 2933.1, which limited conduct credits to 15%, did not impermissibly modify section 190, subdivision (a), which had previously allowed for 50% credit.