A federal judge on Friday dismissed a libel lawsuit filed against The New York Times by a former Army scientist once identified as a person of interest in the 2001 anthrax attacks. U.S. District Judge Claude Hilton in Alexandria dismissed the case a week after lawyers for the Times argued that Steven Hatfill should be considered a public figure under libel law, which makes it much more difficult for a public figure to win a judgment than a private citizen. The judge did not explain his ruling in the order issued Friday. Hatfill had claimed that a series of columns falsely implicated him as the culprit in the anthrax attacks. Kristof said all along that he never intended to accuse Hatfill but simply wanted to prod a dawdling FBI investigation. He initially referred to Hatfill in his columns only as Mr. X," and identified him by name only after Hatfill held a news conference to denounce rumors that had been swirling around him. Hatfill argued that the columns contained enough information about him that people could deduce his identity. Five people were killed and 17 sickened by anthrax that had been mailed to lawmakers on Capitol Hill and members of the news media in New York and Florida just weeks after the Sept. 11, 2001, terrorist attacks. The case remains unsolved.