Does section 28 and 29 of the Mental Health Act prohibit a defendant from presenting evidence in support of his mental state defense?

"[T]hese sections 'do not preclude offering as a defense the absence of a mental state that is an element of a charged offense or presenting evidence in support of that defense. They preclude only expert opinion that the element was not present.' " (People v. Herrera, supra, 247 Cal.App.4th at p. 476, quoting People v. Coddington (2000) 23 Cal.4th 529, 583.) " 'Put differently, sections 28 and 29 do not prevent the defendant from presenting expert testimony about any psychiatric or psychological diagnosis or mental condition he may have, or how that diagnosis or condition affected him at the time of the offense, as long as the expert does not cross the line and state an opinion that the

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