Does the rule that prevents a killer from profiting by his own wrong should not be invoked in such a way as to prejudice the rights of the other beneficiary?

"The rule that prevents [the killer from] profiting by his own wrong should not be invoked in such a way as to prejudice the rights of the alternative beneficiary. 'In a word, it appears to me that the crime of one person may prevent that person from the assertion of what would otherwise [234 Cal.App.3d 1693] be a right, and may accelerate or beneficially affect the rights of third persons, but can never prejudice or injuriously affect those rights.' [Citations.]" (Beck v. West Coast Life Ins. Co., supra, 38 Cal.2d at p. 647, 241 P.2d 544.)