Dr. Mayes found clues about what the two people had been like in life. One was a man who died in his mid- to late 20s. He had a strong right arm that he may have built up through the use of a spear thrower. The other, a woman in her late 30s or early 40s, had teeth that showed signs of having been worn down by stripping fibers for making baskets.

“She used her teeth as tools,” Dr. Mayes said.

The University of California, for its part, appointed a committee of professors to evaluate the tribes’ claim. In 2008, they concluded that the skeletons were “culturally unidentifiable.” The grave contained no objects that might have established a cultural link, and the committee found no compelling evidence that these were ancient relatives of the Kumeyaay people.

Even so, Dr. Bettinger, a member of the committee, said in an interview that he grew concerned that the university would rush a transfer of the skeletons, and that the Kumeyaay would deny access.

So in 2010, he asked the university for permission to study the remains. So did Margaret J. Schoeninger, an anthropologist at the University of California, San Diego, and Tim D. White of the University of California, Berkeley. Dr. Schoeninger was denied, and Dr. Bettinger and Dr. White say they never received a response.

Instead, the University of California announced that in 2011, the skeletons would be given to the La Posta Band, one of the Kumeyaay bands. Dr. Bettinger, Dr. Schoeninger and Dr. White sued to stop the transfer, arguing that the university had not made an adequate finding about the skeletons.

Dr. Kemp of Washington State, who filed an amicus brief on behalf of the scientists, said the university had failed to meet the requirements of the repatriation act. “The law hasn’t been followed,” he said.

But the court arguments didn’t directly address the university’s actions or the scientific importance of the skeletons. The University of California argued that the Kumeyaay bands had to be joined in the suit. Because the bands had tribal immunity, the university argued, the scientists couldn’t sue them.