Washington (CNN) -- Attorney General Eric Holder challenged his leading Republican critics Wednesday over the handling of the failed Christmas Day bomber, defending his decision to provide the suspect with Miranda warnings and charge him in a civilian court.
In identical letters to Senate Minority Leader Mitch McConnell and 10 other top Senate Republicans, Holder said he acted with the knowledge and consent of other relevant government departments and agencies in deciding against treating suspect Umar Farouk AbdulMutallab as an enemy combatant.
Holder also noted that similar past decisions on terrorism suspects by previous administrations of both parties received no criticism.
"The decision to charge Mr. AbdulMutallab in federal court, and the methods used to interrogate him, are fully consistent with the long-established and publicly known policies and practices of the Department of Justice, the FBI, and the United States government as a whole, as implemented for many years by administrations of both parties," Holder's letter said.
"Those policies and practices, which were not criticized when employed by previous administrations, have been and remain extremely effective in protecting national security," the letter said. "They are among the many powerful weapons this country can and should use to win the war against al Qaeda."
Holder's letter said he personally made the decision on the handling of AbdulMutallab, who was taken into federal custody after the U.S. airliner he allegedly sought to bomb landed in Detroit.
"I made the decision to charge Mr. AbdulMutallab with federal crimes and to seek his detention in connection with those charges, with the knowledge of, and with no objection from all other relevant departments of the government," Holder said.
Republicans have severely criticized Holder for the decision to inform the terrorism suspect of his Miranda rights after less than an hour of questioning by the FBI.
The Justice Department also was criticized for failing to promptly consult with the leaders of other national security and intelligence agencies before deciding to push the case into a civilian criminal court.
"Some have argued that had AbdulMutallab been declared an enemy combatant, the government could have held him indefinitely without providing him access to an attorney. But the government's legal authority to do so is far from clear," Holder wrote.
The attorney general's defense followed sharp Republican criticism at a Senate Intelligence Committee hearing Tuesday.
Holder's letter may not satisfy McConnell and other critics.
In a speech Wednesday, McConnell rejected Holder's argument that the administration of President George W. Bush also tried terrorism suspects in civilian courts.
"That's right. It did, and it was wrong to do so," McConnell said of the Bush administration.
In the AbdulMutallab case, "Yemeni forces needed that information on December 25th, not six weeks later," McConnell said of possible intelligence the suspect might have provided if turned over to military interrogators upon his arrest.
Sen. Jeff Sessions of Alabama, the top-ranking Republican on the Senate Judiciary Committee, said Holder "has finally come forward and said he's the one who decided that AbdulMutallab should be treated like a civilian, squandering an invaluable intelligence opportunity."
Sessions called the letter "insufficient" and said Holder must testify before the committee.
Later Wednesday, Sen. Patrick Leahy of Vermont, the Democratic chairman of the Judiciary Committee, announced Holder will be scheduled to testify before the panel in March.
The partisan sniping over the failed Christmas bombing comes as Republican senators, with some Democratic support, are proposing a bill to cut off money for a civilian trial for another terrorism suspect -- admitted September 11 mastermind Khalid Sheikh Mohammed.
Mohammed remains in custody at the Guantanamo Bay, Cuba, detention facility as administration officials seek a U.S. venue for a civilian trial.
Holder previously announced the trial of Mohammed and four other suspects in the case would be held in New York City, but the administration is reconsidering that venue after concerns about costs and logistics raised by New York Mayor Michael Bloomberg and other officials.
In addition, congressional Republicans and some Democrats have opposed bringing the suspects to U.S. soil for a trial.