Before considering a charge against any person, the foreman of the grand jury shall state to those present the matter to be considered and the person to be charged with an offense in connection therewith. He shall direct any member of the grand jury who has a state of mind in reference to the case or to either party which will prevent him from acting impartially and without prejudice to the substantial rights of the party to retire. Any violation of this section by the foreman or any member of the grand jury is punishable by the court as a contempt.
Ca. Pen. Code § 939.5