Court Lets U.S. Resume Paying for Embryo Study

The 2-to-1 ruling, by a panel of judges from the United States Court of Appeals for the District of Columbia Circuit, blocks a lower-court decision last August holding that such research is illegal under a law that bans public spending on research in which human embryos are damaged or destroyed.

The stem cells are derived from donated human embryos left over from fertility treatments; the embryos are destroyed in the process, leading some opponents of abortion to liken the research to murder.

But the appellate court said Friday that because the law is written in the present tense, “it does not extend to past actions.”

Samuel B. Casey, a lawyer for two scientists who sued the government to stop paying for research into human embryonic stem cells, said that he was “a little disappointed” but also pleased that the appeals court kept his suit alive, and that he was considering an appeal.

Representative Diana DeGette, Democrat of Colorado, said she was “extremely pleased with this decision.” But she promised to push for unambiguous legislation that would allow such research to continue.

The ruling sends the case back to Chief Judge Royce C. Lamberth of Federal District Court in Washington, who concluded in August that the Obama administration was so unlikely to win the case that he issued an immediate ban on any federal spending on human embryonic research.

That decision shocked government scientists, who said it would force the cancellation of dozens of experiments on an array of diseases, from diabetes to Parkinson’s. The government appealed, and the appeals court stopped the ban from going into effect while it heard arguments in the case. Friday’s ruling is the end of the first phase of the litigation.

“This is a momentous day not only for science but for the hopes of thousands of patients and their families who are relying on N.I.H.-funded scientists to pursue life-saving discoveries and therapies that could come from stem cell research,” said Dr. Francis S. Collins, director of the National Institutes of Health.

David A. Prentice of the Family Research Council, an anti-abortion group, said he was disappointed. “Federal taxpayer funds should go towards helping patients first, not unethical experiments,” he said.

The research potential for embryonic stem cells, which were discovered in 1998, arises from their ability to morph into any cell in the body and possibly form new organs.

President George W. Bush was the first to allow federal financing of human embryonic stem cell research, but he limited the research to 21 cell lines already in existence to discourage further destruction of embryos.

President Obama promised in his campaign to expand the research and ordered the health institutes soon after his inauguration to do just that.

Judge Lamberth’s ruling was so sweeping that the Obama administration interpreted it as a ban on all stem cell research, including projects that passed muster under his predecessor.

Dr. George Q. Daley, director of the stem cell transplant program at Children’s Hospital Boston, said he was happy with the ruling. “But it’s tempered by the fact that there’s a court case that is still pending,” he added.

Dr. Daley’s laboratory is using embryonic stem cells to research cures into bone marrow failure, a rare genetic condition sometimes called “bubble boy disease” because it forces children to live in sterile environments.

His lab is also comparing the relative properties of embryonic stem cells and so-called pluripotent stem cells derived from adult tissue; some anti-abortion activists say the pluripotent cells, which have the potential to turn into the many kinds of specialized cells in the body, are an ethical alternative to the embryonic kind.

The plaintiffs in the case are two scientists, Theresa Deisher and Dr. James L. Sherley, who use only adult stem cells in their research. They argue that the administration’s policy puts their own research at a disadvantage in the competition for government financing.

Judge Karen LeCraft Henderson, the dissenter in Friday’s appeals court ruling, wrote that her colleagues “perform linguistic jujitsu” to arrive at their conclusion.

The plain language of the law bars financing for all research that follows the destruction of embryos, she wrote, and it is meaningless to try to separate the process of destruction from the use of the stem cells that result from that destruction.

Mr. Casey, the lawyer for the plaintiffs, said Judge Henderson’s dissent might lead him to ask the full Court of Appeals to reconsider the case.

“But my mother told me to always sleep on these things, so that’s what we’re going to do,” he said.