On March 5, 2003, Substitute House Bill (SHB) 1828 was read in the legislature of the state of Washington. The legislation would require insurance companies to provide comprehensive parity for mental health services, meaning they are delivered under the same terms and conditions as medical and surgical services. According to the substitute bill, mental health services means 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. The following mental health services are not to be covered under the bill: Substance related disorders; life transition problems (referred to as V codes); sexual dysfunction disorders; skilled nursing facilities, home health care, residential treatment, and custodial care; and court ordered treatment unless medically necessary.

The bill would apply to all health benefit plans in the state of Washington. 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 health benefit plan. Also, prescription drugs intended to treat any of the disorders included in the bill must also be under the same terms and conditions as other prescription drugs covered by the health benefit plan. The bill calls for the same maximum out-of-pocket limits and the removal of arbitrary day and visit limits as well. Further, the parity bill requires a single annual deductible for mental health and other health services and the same annual and lifetime dollar limits.