What is the test for determining whether a defendant acted in self-defense?

We first address defendant's contention that the prosecution failed to meet its burden of proving beyond a reasonable doubt that he was not acting in self-defense. As explained ante, the burden is on the prosecution to prove beyond a reasonable doubt that defendant did not act in self-defense or with another legal justification. However, defendant asserts that since there was evidence that supports his self-defense claim, we must find the evidence was insufficient to support a contrary finding and his manslaughter conviction must be reversed. This assertion is incorrect. " 'The test on appeal is whether there is substantial evidence to support the conclusion of the trier of fact; it is not whether guilt is established beyond a reasonable doubt. [Citation.]' [Citations.]" (People v. Gray (1998) 66 Cal.App.4th 973, 983-984; People v. Liu (1996) 46 Cal.App.4th 1119, 1131-1132.)