(1) For the purposes of this section, "mental health services" means:
(a) For any schedule of benefits established or renewed by the Washington basic health plan before January 1, 2021, medically necessary outpatient and inpatient services provided to treat mental disorders covered by the diagnostic categories listed in the most current version of the diagnostic and statistical manual of mental disorders, published by the American psychiatric association, on June 11, 2020, or such subsequent date as may be determined by the director, by rule, consistent with the purposes of chapter 6, Laws of 2005, with the exception of the following categories, codes, and services: (i) Substance related disorders; (ii) life transition problems, currently referred to as "V" codes, and diagnostic codes 302 through 302.9 as found in the diagnostic and statistical manual of mental disorders, 4th edition, published by the American psychiatric association; (iii) skilled nursing facility services, home health care, residential treatment, and custodial care; and (iv) court ordered treatment, unless the Washington basic health plan's or contracted managed health care system's medical director or designee determines the treatment to be medically necessary; and
(b) For any schedule of benefits established or renewed by the Washington basic health plan on or after January 1, 2021, medically necessary outpatient and inpatient services provided to treat mental health and substance use disorders covered by the diagnostic categories listed in the most current version of the diagnostic and statistical manual of mental health or substance use disorders, published by the American psychiatric association, on June 11, 2020, or such subsequent date as may be determined by the director by rule, consistent with the purposes of chapter 6, Laws of 2005.
(2) Any schedule of benefits established or renewed by the Washington basic health plan shall provide coverage for:
(a) Mental health services. The copayment or coinsurance for mental health services may be no more than the copayment or coinsurance for medical and surgical services otherwise provided under the schedule of benefits. Wellness and preventive services that are provided or reimbursed at a lesser copayment, coinsurance, or other cost sharing than other medical and surgical services are excluded from this comparison. If the schedule of benefits imposes a maximum out-of-pocket limit or stop loss, it shall be a single limit or stop loss for medical, surgical, and mental health services. If the schedule of benefits imposes any deductible, mental health services shall be included with medical and surgical services for the purpose of meeting the deductible requirement. Treatment limitations or any other financial requirements on coverage for mental health services are only allowed if the same limitations or requirements are imposed on coverage for medical and surgical services; and
(b) Prescription drugs intended to treat any of the disorders covered in subsection (1) of this section to the same extent, and under the same terms and conditions, as other prescription drugs covered under the schedule of benefits.
(3) This section does not prohibit a requirement that mental health services be medically necessary, if a comparable requirement is applicable to medical and surgical services.
(4) Nothing in this section shall be construed to prevent the management of mental health services if a comparable requirement is applicable to medical and surgical services.