WASHINGTON (AP) -- Talk about going out with a win.

Sen. Pete Domenici, R-N.M., has spent years fighting for legislation that would require insurance plans to treat mental health patients on par with those who have physical ailments. No more higher copays or deductibles for the mental health treatments. No more limits on visits to the doctor that differ from the caps for other patients.

Domenici, after six terms, is leaving office this year. One of his final votes was on the mental health legislation he fought so hard for over the years.

The mental health protections are part of a massive bill designed to help the economy. Dominici senses that somehow the bill will become law, even though many lawmakers from both parties are unhappy with the economic bailout.

Domenici has a daughter diagnosed with atypical schizophrenia. He got involved in the parity issue after joining a National Alliance on Mental Illness support group nearly 20 years ago. On his way home from work, he and his wife, Nancy, would meet with other parents of children with mental health problems.

"The first real understanding of how broad the problem was came from those meetings where I met with mothers and fathers who had children who were mentally ill, and they were going bankrupt because they couldn't pay the health bills, or their children were in jails instead of hospitals," Domenici said.

He said perceptions about the ability to treat mental health problems have changed greatly over the years, but coverage has also become an expensive proposition. So, he and others, such as the late Sen. Paul Wellstone, D-Minn., began pushing for health insurance parity. Pushback came from those who would have to bear most of the expense.

"Those who stood to lose fought hard and that was principally insurance companies and businesses," Domenici said.

Employers and insurers were concerned that legislation would have required plans to cover a "telephone book" of conditions, raising costs beyond what companies and their workers could afford and potentially negating companies' ability to offer any health coverage at all.

The legislation now before the House does not mandate that group health plans cover mental health or addiction treatment, only that when plans do so, the coverage must be equitable to other medical coverage. The insurance industry is now a strong supporter of the parity legislation.

In 1996, Sens. Wellstone and Domenici won passage of a law banning insurance plans that offer mental health coverage from setting lower annual and lifetime spending limits for mental treatments than for physical ailments.

The pair again teamed up in 2001 on a predecessor to the legislation now before the House. After Wellstone was killed in a plane crash in 2002, Sens. Edward Kennedy, D-Mass., and Mike Enzi, R-Wyo., took on larger roles in getting a bill passed in the Senate.

The requirement for equal treatment in insurance coverage would apply to health plans that cover more than 50 employees -- potentially reaching 113 million people nationwide.

Health officials contend that equal protections for mental health conditions would lead to a healthier, more productive work force.

"There's a phenomenon ... where you've got a psychiatric illness and you're able to get around but you can't do your work at the same quality you did before," said Dr. Nada Stotland, president of the American Psychiatric Association.

"Many workers today are in the service industry. If a person on the other end of the line is depressed, they may have shown up to work and they may be present, but they will not necessarily make us happy about the company that we're calling. They'll be slow, unhappy and maybe irritable, and their powers of concentration won't be good. So, more and more companies want to see their employees treated."

Overall, the parity legislation is expected to cost the federal government about $3.4 billion over 10 years. That's because employers will have more health expenses that they can deduct from their income taxes.

Copyright 2008 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.