Legal Question in Constitutional Law in California

Re: how many jurors?

In California state courts (Superior Court), 9 out of 12 (or 3/4).

In California federal courts, 12 out of 12 (unanimous verdict required).

In all criminal courts, unanimous verdict required.

Rarely a court will impanel fewer than 12 jurors, for example on occasion in the federal courts we have heard of 8-juror civil panels. The same proportions (3/4 in state, 100% in Federal) would apply.

Re: how many jurors?

I agree with Mr. Stone's answer, but there is one point I wan to add. In order to get a jury you need to demand one in the proper way and at the proper time. If you don't, your case will be decided by the judge. There are many reasons why you might prefer a judge instead of a jury, but if you don't follow the correct procedures the decision will be made for you.