The U.S. Senate Indian Affairs Committee has slipped a landmark change into a routine housekeeping bill that could affect the 9,300-year-old remains known as Kennewick Man.

The change could pave the way for modern tribes to file a new claim for the remains found 11 years ago on the shores of the Columbia River in southeastern Washington. It also could preclude respectful study of other very old remains that might help shed more light on the evolving view of America's distant past and early migration.

Washington Sen. Maria Cantwell, a committee member, voted for the bill. The committee tucked an amendment to the Native American Graves Protection and Repatriation Act into a technical corrections measure. Currently, the repatriation law defines "Native American" as "of, or relating to, a tribe, people, or culture that is indigenous to the United States." The amendment would add two words so it reads: "... is, or was, indigenous. ... " That means tribes could claim remains with no discernible link to them except they were found in an area where the tribes live.

The existing wording was pivotal when prominent scientists won the right to study Kennewick Man in federal court. Led by Doug Owsley of the Smithsonian National Museum of Natural History, they sued after the Army Corps of Engineers moved to give the remains to Columbia Plateau tribes that claimed him as an ancestor. The final report could be released in 2009.

Federal courts held the law required modern tribes to prove a legally plausible connection to the ancient remains, but the tribes who sought to bury Kennewick Man could not prove one. At the time, limited studies found the remains more closely resembled the Ainu of Japan than modern Native American tribes.

The repatriation law is a righteous law requiring remains and sacred objects to be returned to modern Native Americans where a connection can be established.

But Kennewick Man and other remains of this age — found and yet to be found — can help shed light on the unfolding story of early America. Within the past two decades, scholars increasingly have given more weight to theories that early America was populated in several waves of migration from Asia and earlier than previously thought.

Enacted in 1990, NAGPRA was considered a compromise to balance the rights of Native Americans to their ancestors and sacred objects with the interests and public benefit of scientific inquiry.

This amendment tips that balance. It should not be enacted.