Vice President Dick Cheney said on Friday that his indicted ex-chief of staff, Lewis Libby, was presumed innocent until a contrary finding is made by a jury. In a written statement, Cheney said he had accepted Libby's resignation with deep regret. "In our system of government an accused person is presumed innocent until a contrary finding is made by a jury after an opportunity to answer the charges and a full airing of the facts. Mr. Libby is entitled to that opportunity," he said.