What is sufficient evidence to prove kidnapping was an independent felonious purpose in a murder case?

Here, the relationship between the homicide and the kidnapping is undeniable. The kidnapping was merely incidental to the homicide. No other conclusion is reasonable. (Cf. People v. Raley (1992) 2 Cal.4th 870, 902-903 [sufficient evidence proved kidnapping independent felonious purpose because defendant "may have been undecided as to [victims'] fate at" time of kidnapping, and may have "formed the intent to kill after" kidnapping commenced, "so that the kidnapping could not be said to be merely incidental to the murder."].)

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