Form of verdict in certain cases involving insanity or mental disease or defect.

(a) In a prosecution for a crime when the affirmative defense of insanity is raised under AS 12.47.010 , or when evidence of a mental disease or defect of the defendant is otherwise admissible at trial under AS 12.47.020 , the trier of fact shall find, and the verdict shall state, whether the defendant is (1) guilty; (2) not guilty; (3) not guilty by reason of insanity; or (4) guilty but mentally ill. (b) To return a verdict under (a)(4) of this section, the fact finder must find beyond a reasonable doubt that the defendant committed the crime and that, when the defendant committed the crime, the defendant was guilty but mentally ill as defined in AS 12.47.030 . (c) When the jury is instructed as to the verdicts under (a) of this section, it shall also be instructed on the dispositions available under AS 12.47.050 and 12.47.090.