What is the effect of a modification to a jury's instructions on voluntary manslaughter?

The modification was erroneous. "[I]f the fact finder determines the killing was intentional and unlawful, but is not persuaded beyond reasonable doubt that [sufficient] provocation (or imperfect self-defense) was absent, it should acquit the defendant of murder and convict him of voluntary manslaughter. [Citations.]" (People v. Rios (2000) 23 Cal.4th 450, 462.) Appellant argues that the modification was reversible error because it "foreclosed a guilty verdict on voluntary manslaughter, forcing the jury to make an all-or-nothing choice between murder or acquittal. The error was equivalent to not instructing the jury at all on voluntary manslaughter." (Italics added.)

"A challenged instruction is not viewed '"in artificial isolation,"' but is considered in the context of the instructions as a whole and the entire record. [Citation.] We are . . . obligated to regard the [jury] as intelligent and capable of understanding and correlating all instructions they are given. [Citation.]" (People v. Mehserle (2012) 206 Cal.App.4th 1125, 1155, fn. omitted; see also Middleton v. McNeil (2004) 541 U.S. 433, 437 [124 S.Ct. 1830, 158 L.Ed. 2d 701] (Middleton) ["'"[A] single instruction to a jury may not be judged in artificial isolation, but must be viewed in the context of the overall charge"'"].)