NEW YORK (Reuters) - A U.S. judge ordered the Central Intelligence Agency on Thursday to submit to the court a 2002 memo said to specify harsh interrogation methods used on suspected terrorists held abroad.

The American Civil Liberties Union said the memo was written by the Department of Justice’s Office of Legal Counsel and sent to the CIA in August 2002. The ACLU described the memo as “one of the most important torture documents still being withheld by the Bush administration.”

In a copy of the order posted on the ACLU’s Web site, Judge Alvin Hellerstein told the government to produce the memo so he can determine whether it should be made public as part of a lawsuit the ACLU and other organizations filed in June 2004 requesting records concerning the treatment of prisoners in U.S. custody abroad.

Hellerstein has scheduled a review of the document for Monday.

“This memo authorized the CIA to use specific torture techniques -- including waterboarding,” Jameel Jaffer, ACLU’s national security project director, said in a statement.

“CIA agents waterboarded prisoners because this memo told them that they could,” he said. “The memo is being withheld not for legitimate security reasons, but in order to protect government officials from accountability for their decisions.”

Waterboarding is a simulated drowning technique.

The ACLU said more than 100,000 pages of government documents have been released in response to its lawsuit.

Among those was a declassified 2003 memo, released by the U.S. Justice Department on April 1, that justified the use of harsh interrogation methods for suspected terrorists held abroad.

A subsequent decision overruled the memo, which said President George W. Bush’s authority as commander-in-chief superseded international law regarding wartime interrogations.

The U.S. military has banned the use of waterboarding and other harsh methods considered by some rights advocates to be torture. The U.S. intelligence community has not.

Bush authorized the CIA to use waterboarding after the September 11 attacks in 2001, but he has repeatedly insisted that the United States does not torture prisoners.

The CIA has said it used waterboarding during the interrogations of Khalid Sheikh Mohammed, who faces murder charges in the U.S. military court at Guantanamo Bay, Cuba.