Does a jury have a constitutional right to determine every material issue presented by the evidence at trial?

1 Although a defendant has a constitutional right to have the jury determine every material issue presented by the evidence, and an improper refusal of instructions on a defense theory supported by the evidence has been deemed reversible per se (People v. Modesto (1963) 59 Cal.2d 722, 730, 31 Cal.Rptr. 225, 382 P.2d 33; but see People v. Sedeno (1974) 10 Cal.3d 703, 720-721, 112 Cal.Rptr. 1, 518 P.2d 913), in the present case the jury was instructed, albeit contradictorily, on the subject of specific intent to kill. Accordingly, no Modesto error was committed here.