Utah Code § 77-10a-18: Grand jury term of service -- Excusing a juror.

(1) A grand jury shall serve until discharged by the managing judge. However, a grand jury may not serve more than 18 months unless the managing judge extends the service of the grand jury, upon determining an extension is in the public interest. The extension may be no longer than a period of six months.

(2) The managing judge may at any time excuse a juror either temporarily or permanently for cause shown. If a juror is excused permanently, the managing judge may impanel another juror in that juror's place.