WASHINGTON (Reuters) – The U.S. Chamber of Commerce filed a lawsuit on Thursday against the Federal Trade Commission that accuses it of unlawfully withholding public records. “The opacity of commission operations have created a ‘black-box environment’ that increases uncertainty for businesses,” the business group said in a statement. The Chamber, which speaks for U.S. businesses, has been critical of the FTC under Chair Lina Khan, who has support among progressive Democrats. In a court filing, the Chamber said that it wanted to compel compliance with Freedom of Information Act requests for pub…