What is the test for a defendant who claims to have used force "to be in self-defense" under section 1103, subdivision (a) of the California Criminal Code?

The essence of defendant's argument on appeal is that his BB gun incident testimony was not really section 1103, subdivision (a), evidence. Instead, the BB gun incident testimony was directly relevant to defendant's state of mind on June 27 and the objective reasonableness of defendant's subjective belief that he needed to defend himself. (See People v. Humphrey (1996) 13 Cal.4th 1073, 1082 [For use of force "to be in self-defense, the defendant must actually and reasonably believe in the need to defend"]; People v. Minifie (1996) 13 Cal.4th 1055, 1060 ["A defendant charged with assaultive crimes who claims self-defense may present evidence that the alleged victim had previously threatened him"]; People v. Garvin (2003) 110 Cal.App.4th 484, 488 [upon request, jury must be instructed with regard to "the effect of the victim's antecedent threats or assaults against the defendant on the reasonableness of defendant's conduct"].)