No detention of minors after eighteenth birthday—Exceptions.

No minor received as a voluntary patient or committed under this chapter may be detained after his or her eighteenth birthday unless the person, upon reaching eighteen years of age, has applied for admission to an appropriate evaluation and treatment facility or unless involuntary commitment proceedings under chapter 71.05 RCW have been initiated: PROVIDED, That a minor may be detained after his or her eighteenth birthday for purposes of completing the fourteen-day diagnosis, evaluation, and treatment.[ 1985 c 354 s 20. Formerly RCW 71.34.190.]