RCW 9A.12.010
Insanity.
To establish the defense of insanity, it must be shown that:
(1) At the time of the commission of the offense, as a result of mental disease or defect, the mind of the actor was affected to such an extent that:
(a) He or she was unable to perceive the nature and quality of the act with which he or she is charged; or
(b) He or she was unable to tell right from wrong with reference to the particular act charged.
(2) The defense of insanity must be established by a preponderance of the evidence.
[ 2011 c 336 § 353; 1975 1st ex.s. c 260 § 9A.12.010.]
Structure Revised Code of Washington