The proposed measure, which would capitalize on an earlier law, would open the door for mental health patients to receive health insurance benefits on par with non-mental disorder benefits.
"Our country must make a commitment," Bush told an audience at the University of New Mexico. "Americans with mental illnesses deserve our understanding, and they deserve excellent care."
Bush said the 15-person New Freedom Commission on Mental Health would identify the needs of patients, current barriers to care, and also investigate community-based care programs that have success in coordinating and providing mental health services.
The commission will have one year to make its recommendations.
Congress is considering legislation that would grant benefit parity, but its opponents argue parity would result in increased premiums.
The Domenici-Wellstone Mental Health Equitable Treatment Act, approved by the Senate Health Education Labor and Pensions Committee, is supported by more than 160 national organizations, bill advocates say.
Bush has long supported parity legislation. As governor of Texas, he signed legislation into law that required health insurers not to shortchange people suffering from severe mental illnesses.
"As many Americans know, it is incredibly painful to watch someone you love struggle with an illness that affects their mind and their feelings and their relationships with others," Bush said.
"Remarkable treatments exist, and that's good. Yet many people -- too many people -- remain untreated. Some end up addicted to drugs or alcohol. Some end up on the streets, homeless. Others end up in our jails, our prisons, our juvenile detention facilities.
"Our country must make a commitment: Americans with mental illness deserve our understanding, and they deserve excellent care," he said. "They deserve a healthcare system that treats their illness with the same urgency as a physical illness."
Sen. Paul Wellstone, D-Minn., later thanked the president for his support.
"We have the opportunity to make mental health parity a reality in this session, and I urge the president to work closely with members in both the Senate and the House to get this done as quickly as possible," he said.
"The time to move on this legislation is now."
The Wellstone-Domenici Mental Health Equitable Treatment Act of 2001 (named for Wellstone and Sen. Pete Domenici, R-N.M.) builds on the senators' 1996 landmark legislation to ensure greater parity in the coverage of mental illness. It bars group health plans from treating mental health benefits differently from the coverage of any other medical or surgical benefits. As with federal workers, there would be full parity for all cost-related and access-related benefits for all categories of mental health conditions listed in the Diagnostic and Statistical Manual of Mental Disorders, Wellstone's office said.
The bill does not mandate the coverage of mental health benefits. Instead, it rather requires all insurance companies that list coverage of mental illness as a part of their benefit packages to provide those services with no greater cost or access limitation than are required for other medical illnesses.
The president said three obstacles were blocking the road ahead and had to be overcome: the stigma placed on mental illness; a fragmented treatment delivery system that allows sufferers to fall through the cracks and not receive treatment; and unfair treatment limitations placed on mental health by insurers.
"Stigma leads to isolation, and discourages people from seeking the treatment they need," Bush said. "Political leaders, healthcare professionals, and all Americans must understand and send this message: Mental disability is not a scandal -- it is an illness."
He said the commission would help close the gaps in diagnosis and treatment. Proposed legislation will insure that the health insurance system "treat mental illness like any other disease."
Michaelo Faenza, president of the National Mental Health Association, said in a statement Monday that "mental health parity is very much a civil rights issue; passage of mental health parity legislation is long overdue in America."