What is the standard of "harmless beyond a reasonable doubt" in a motor vehicle accident case?

The prejudice standard of "harmless beyond a reasonable doubt" of Chapman v. California (1967) 386 U.S. 18, 21, 87 S.Ct. 824, 826, 17 L.Ed.2d 705, is applicable to an error in instruction completely removing the intent element of a crime from the jury's consideration and to contradictory and irreconcilable instructions on intent. (People v. Lee (1987) 43 Cal.3d 666, 671-676, 238 Cal.Rptr. 406, 738 P.2d 752.) The error in the instant case was clearly prejudicial under this test. Indeed, had the jury been properly instructed, it is reasonably probable that the jury would have concluded that defendant did not appreciate the risk to life [49 Cal.3d 1229] created by his conduct although he should have done so and that he was guilty of involuntary manslaughter rather than second degree murder.