(Reuters) - The Obama administration on Monday pushed backed against Republican accusations that Attorney General Eric Holder lied during a congressional appearance last month about his involvement in leak investigations that involved reporters. Republican lawmakers have called Holder's credibility into question by alleging that he failed to tell the truth in testimony to the House of Representatives Judiciary Committee about the Justice Department's secret seizures of journalist records.Holder told the committee on May 15 that he was not involved in the potential prosecution of a reporter under the 1917 Espionage Act. Reports later surfaced that he had signed off on...