Is mistaken belief about the lawfulness of police custody a defense to an attempted violation of section 405a?

Third, recognizing a mistaken belief about the lawfulness of police custody as a defense to an attempted violation of section 405a would violate public policy. The defense of mistake of fact is not appropriate where its recognition would excuse behavior that violates a strong public policy. (See Branch, supra, 184 Cal.App.4th at p. 522, 109 Cal.Rptr.3d 412 ; People v. Olsen (1984) 36 Cal.3d 638, 646, 205 Cal.Rptr. 492, 685 P.2d 52 ( Olsen ) [declining to recognize the defense of reasonable mistake about the victim's age in a prosecution for lewd or lascivious conduct with a minor under the age of 14 because doing so would contradict the "strong public policy to protect children of tender years"].)