Penal Code Section 90
Consent known to be given under fear or misconception and consent of a child or person of unsound mind
90. A consent is not such a consent as is intended by any section of this Code—
(a) if the consent is given by a person under fear of injury, or under a misconception of fact, and if the person doing the act knows, or has reason to believe, that the consent was given in consequence of such fear or misconception;
b) if the consent is given by a person who, from unsoundness of mind or intoxication, is unable to understand the nature and consequence of that to which he gives his consent; or
(c) unless the contrary appears from the context, if the consent is given by a person who is under twelve years of age.
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