WASHINGTON (Reuters) - An aide to U.S. Senate Majority Leader Bill Frist has resigned amid a probe into how Republican staffers gained access to sensitive Democratic computer files, a spokeswoman for Frist said on Thursday.She said Manuel Miranda resigned after an investigation into the leak of files on Democratic strategy on resisting some of President Bush's judicial nominees.
Democrats had complained of what they called "improper retrieval and release" of sensitive internal Judiciary Committee Democratic staff documents about the battle over Bush's conservative nominees to federal courts.
The rancorous partisan battle over judges has bogged down the Senate repeatedly over the past year.
Democrats fear that documents were viewed by staff over a period of months. Some were later leaked to conservative newspapers and commentators and at least one Web site.
Senate Judiciary Committee chairman Orrin Hatch, a Utah Republican, last November apologized for any staff improprieties and called the incident an "improper, unethical and simply unacceptable breach of confidential files."
Miranda was a Republican aide on the Judiciary Committee before transferring to Frist's staff and advised him on judicial affairs.
Senate Democratic Leader Tom Daschle of South Dakota said he expected the investigation, by the Senate Sergeant-at-Arms with help from the Secret Service and computer forensic specialists, would be completed by the end of the month.
