E. Lawrence Barcella, Mr. Hsu’s lawyer, said that Mr. Hsu was getting a California lawyer to represent him before the state attorney general. Mr. Barcella declined to comment on where Mr. Hsu was, or on the status of any bench warrants issued against him in that state. “On that matter, he will be represented by California counsel,” Mr. Barcella said.

Investigators believe that after Mr. Hsu skipped his court appearance in 1992, he went to his native Hong Kong and then continued working in the garment trade. At some point, Mr. Hsu, a naturalized American citizen, returned to New York and in 2003 made the first of what became hundreds of thousands of dollars in contributions to Democratic campaigns around the nation.

People who met him said they knew only that he ran an apparel business. Efforts to learn more about his trade hit dead-ends yesterday. Visits to companies at addresses listed by Mr. Hsu on campaign finance records provided little information. There were no offices in buildings in New York’s garment district whose addresses were given for businesses with names like Components Ltd., Cool Planets, Next Components, Coopgors Ltd., NBT and Because Men’s clothing — all listed by Mr. Hsu in federal filings at different times.

At a new loft-style residential condominium in SoHo that was also listed as an address for one of his companies, an employee there said that he had never seen or heard of Mr. Hsu. Another company was listed at a condo that Mr. Hsu had sublet in an elegant residential tower in Midtown Manhattan just off Fifth Avenue, but an employee there said Mr. Hsu moved out two years ago, after having lived there for five years. The employee, who was granted anonymity because he was not authorized to talk about residents, said he recalled that Mr. Hsu had received a lot of mail from the Democratic Party.

Mr. Kerrey said he was introduced to Mr. Hsu about two years ago, and shortly thereafter Mr. Hsu joined the board of governors at the Eugene Lang College for liberal arts at the New School. He joined the university’s board of trustees last July.

“So much of the university is about the immigrant culture, and I liked his personal story, coming from China, and he had an interest in fashion as well,” Mr. Kerrey said. “It all intrigued me.”

He said that the university did not do background checks of prospective trustees, and that he saw no reason to ask Mr. Hsu to resign from its board.