WASHINGTON — Though common-sense Americans have repeatedly raised the issue of tort reform while discussing health-care legislation with members of Congress during town hall meetings, too many lawmakers still stubbornly insist that medical liability lawsuits do not contribute significantly to rising health-care costs. These lawmakers are wrong.

A 2006 Harvard School of Public Health study found that four out of every 10 medical malpractice lawsuits filed in America each year are "without merit." Nonetheless, defending against such lawsuits imposes costs on doctors, hospitals and insurers that are passed on to health-care consumers.

Beyond the obvious costs of litigation, more subtle costs related to the practice of "defensive medicine" also are contributing to runaway health-care inflation.

How much? In a Massachusetts Medical Society survey published last November, 83 percent of Bay State physicians cited the fear of being sued in their decisions to practice defensive medicine.

According to the 900 doctors anonymously surveyed, on average, 18 percent to 28 percent of tests, procedures, referrals and consultations, and 13 percent of hospitalizations, were ordered to avoid lawsuits. All of this adds at least $1.4 billion to annual health-care costs in Massachusetts, and national estimates range as high as $200 billion.

So, as Mississippi Gov. Haley Barbour asks, "If we are trying to make health care more affordable, how can we leave out tort reform?"

Another longer-term concern about leaving tort reform out of comprehensive health-care legislation revolves around a growing need for more primary care physicians.

President Obama's stated desire to emphasize preventive medicine as a means to lower overall health-care costs will, with a growing and aging population, require a greater number of doctors. Yet the Association of American Medical Colleges predicts that the overall shortage of doctors practicing both primary care and high-risk specialties may grow to nearly 125,000 by 2025.

Surely medical schools will find it easier to persuade bright young men and women to pursue careers in medicine if the costly threat of medical liability lawsuits is reined in. The experience of states that have enacted tort reforms bears this out.

Six years ago, Texas was seeing doctors leave the state or retire because of frivolous lawsuits and costly medical malpractice insurance premiums. But Texas has since joined 24 other states by enacting reforms that include a reasonable limit on non-economic damages for pain and suffering of up to $750,000 per incident. This does not limit compensatory awards for calculable lost wages and medical expenses, but it does balance the interests of patients and care providers.

Now, according to Gov. Rick Perry, doctors' insurance rates have declined by an average of 27 percent while the "number of doctors applying to practice medicine in Texas has skyrocketed by 57 percent."

President Obama should reconsider his recently stated opposition to limiting non-economic damages in medical liability litigation. The president and Congress also should consider additional liability reforms.

If comprehensive health care reforms are to succeed, they must include liability reform. Certainly real victims of negligence must be fairly compensated, but public policy must discourage litigation that abuses our civil justice system and makes health care less accessible and more expensive.

Sherman Joyce is president of the American Tort Reform Association.