Utah Const. art. I, § 10

[Trial by jury.] In capital cases the right of trial by jury shall remain inviolate. In capital cases the jury shall consist of twelve persons, and in all other felony cases, the jury shall consist of no fewer than eight persons. In other cases, the Legislature shall establish the number of jurors by statute, but in no event shall a jury consist of fewer than four persons. In criminal cases the verdict shall be unanimous. In civil cases three-fourths of the jurors may find a verdict. A jury in civil cases shall be waived unless demanded.