HARRISBURG -- Legal devices like living wills and power of attorney are supposed to make it easier for families to answer heart-rending questions about the level of care for terminally ill relatives.

But if patients haven't formally declared their end-of-life wishes, or identified who should implement them if they are incapacitated, emotional disputes can ensue.

Legislation intended to provide better guidance for families whose loved ones lack either living wills or power of attorney is awaiting Gov. Ed Rendell's signature after being approved unanimously by the state House last Monday. It had earlier passed the Senate, also unanimously.

The measure, sponsored by Sen. Stewart J. Greenleaf, R-Montgomery, would give decision-making priority to a patient's spouse, unless a divorce is pending. That would be followed by adult children, parents, siblings, adult grandchildren, or another adult familiar with the patient's preferences and religious and moral values.

Mr. Greenleaf said the legislation has been several years in the making, long before the bitter end-of-life battle involving Terri Schiavo, a severely brain-damaged woman who had formerly lived in Montgomery County, made national news. She died 13 days after her feeding tube was removed in 2005.

"I think it does provide a service for everyone, because they know what they can do and what they can't do," Mr. Greenleaf said.

The measure was crafted in negotiations involving advocates for the disabled, associations representing doctors and lawyers, and faith-based groups. Mr. Greenleaf sought to improve a similar measure that was passed by the General Assembly in 2004 but vetoed by Mr. Rendell.

In his veto message, the governor expressed concerns that the earlier bill would prevent families whose relatives suffer from advanced chronic diseases, such as Alzheimer's, but are not considered terminally ill, from seeking comfort care instead of life support for patients without a living will. He also praised the intent of the bill and encouraged the Legislature to revise it.

The new legislation allows more flexibility for families in those situations, said Dr. Chris Hughes, an intensive-care doctor at St. Clair Hospital in Mt. Lebanon who helped craft the measure.

"The old bill basically said that unless you had a paper, your family couldn't speak for you, and that would have really turned the practice on its head," Dr. Hughes said. "The way the practice has evolved, we always involve families and loved ones, reflecting what the patients would want."

Rendell spokeswoman Amy Kelchner said Wednesday that the governor would need to review the bill before deciding whether to sign it.

The bill also would give developmentally disabled patients faced with life-threatening illnesses greater say in their medical care, advocates said.

"There certainly have been instances in the past where people who were making decisions ... did not value the lives of people with disabilities in the same way that somebody without a disability might have been valued," said Dr. Kit Gorton, a member of the board of The Arc of Pennsylvania.

Dr. Gorton, a former medical director for the state Office of Mental Retardation, said such patients can make some medical treatment decisions, citing the case of a retarded man in his 50s who was diagnosed with prostate cancer. The man knew generally how he wanted to treat the cancer, and medical professionals helped him pick a more specific solution.

"In my mind, that's the perfect process," he said. "The man got to make as much of his own decisions as he could, and the decisions at the next level were made by people who knew him well."