Predictable Outcomes: Judges' decisions are generally more predictable than those of a jury, in which emotions or personal biases can sway. If, for example, you're assigned a judge with a record of showing leniency for mitigating circumstances, your attorney might recommend waiving the jury trial.
The Trial of all Crimes, except in Cases of Impeachment, shall be by Jury; and such Trial shall be held in the State where the said Crimes shall have been committed; but when not committed within any State, the Trial shall be at such Place or Places as the Congress may by Law have directed.
Article I, Section 16 of the State Constitution of California says, “A trial by jury is an inviolate right and shall be secured to all. A jury may be waived in a criminal cause by the consent of both parties expressed in open court by the defendant and the defendant's counsel."
There are various reasons why a defendant might consider waiving their right to a jury trial. For instance, they might aim to resolve the case swiftly or keep it out of the local news. Alternatively, they might have a lengthy criminal record and wish to minimize public exposure.
The failure of a party to serve and file a demand as required by this rule constitutes a waiver by the party of trial by jury. A demand for trial by jury made as herein provided may not be withdrawn without the consent of the parties.
(d) Waiver; Withdrawal. A party waives a jury trial unless its demand is properly served and filed. A proper demand may be withdrawn only if the parties consent.
A motion to vacate specifically asks a judge to cancel something. If a judge or jury convicted you of a crime — or you pleaded guilty — then a motion to vacate might ask the judge to cancel the conviction.
If you cannot serve even if granted a postponement, you may contact your local commissioner of jurors office and ask to be excused from service. The commissioner may ask you to provide documentary proof of the reasons why you need to be excused.