What is the test for a heat of passion defense?

"To be adequate, the provocation must be one that would cause an emotion so intense that an ordinary person would simply react, without reflection. . . . [T]he anger or other passion must be so strong that the defendant's reaction bypassed his thought process to such an extent that judgment could not and did not intervene." (People v. Beltran (2013) 56 Cal.4th 935, 949.) Therefore, instead of asking whether a reasonable person would respond fatally to the provocation, "the question is whether the average person would react in a certain way: with his reason and judgment obscured." (Ibid.)

"The provocative conduct may be physical or verbal, and it may comprise a single incident or numerous incidents over a period of time." (Le, supra, 158 Cal.App.4th at p. 528.) Thus, in People v. Borchers (1958) 50 Cal.2d 321, the court held that a long history between the defendant and the victim was relevant to the issue of a heat of passion defense. "From the evidence viewed as a whole the trial judge could well have concluded that defendant was roused to a heat of 'passion' by a series of events over a considerable period of time: [The victim's] admitted infidelity, her statements that she wished she were dead, her attempt to jump from the car on the trip to San Diego, her repeated urging that defendant shoot her, [her child], and himself on the night of the homicide, and her taunt, 'are you chicken.'" (Id. at pp. 328-329.)