As part of that work, he traveled in 1953 to Britain, France and West Germany. At the secret British military research center at Porton Down, the sons say, Olson witnessed "extreme interrogations" in which "the CIA committed murder" using biological agents Olson had developed.

They say a psychiatrist there, William Sargent, grew concerned that Olson "had serious misgivings related to those murders and might therefore pose a security risk," and so recommended to his superiors that Olson no longer be granted access to classified research facilities in Britain.

Unwitting guinea pig

Back from Europe, Olson joined colleagues from the Special Operations Division and the CIA at a conference at Deep Creek Lake in Garrett County.

After dinner there on Nov. 19, 1953, CIA chemist Sidney Gottlieb and his deputy served Olson and several others a bottle of Cointreau laced with LSD, according to the Church Committee report. The researchers did not tell their subjects they were being drugged until after they had ingested it.

Five days later, Olson told his supervisor, Army Col. Vincent Ruwet, that he wanted to resign. According to his sons, his decision was based on "ethical concerns regarding the CIA's conduct, including the extreme interrogations he had witnessed and the experiment at Deep Creek Lake."

Ruwet contacted Gottlieb and his deputy, Robert Lashbrook, and the men took Olson to New York, ostensibly to be examined by a doctor who had experience with LSD, according to the Church Committee report. Before they left, Ruwet told Olson's wife, Alice, that he might be dangerous to his family. His sons say he had never been violent.

On Nov. 27, Dr. Harold Abramson recommended that Olson be returned to Maryland for psychiatric treatment. Olson called his wife to tell her he was headed home.

Early the next morning, he fell from the window of the room he was sharing with Lashbrook.

Interviewed by The Baltimore Sun in 2004, Eric Olson recalled the subsequent visit from Ruwet, his father's boss and friend.

"Everybody had this stony-faced expression," Olson said. "I remember Ruwet saying, 'Your father was in New York and he had an accident. He either fell out the window or jumped.'"

Within two weeks, the CIA's general counsel had formed a conclusion: Olson's death was "the result of circumstances arising out of [the Deep Creek Lake] experiment," and there was a "direct causal connection between that experiment and his death."

But the finding was classified. The CIA told the family only that Olson had died during the course of his official duties, without mentioning LSD. The family began to receive death benefits under the Federal Employees Compensation Act.

After Olson's death, Ruwet began visiting their mother regularly for drinks. "Thus began the alcoholism that would torment [her] for the rest of her life," the sons say in the suit.

Growing suspicions

In 1975, a commission appointed by Ford to investigate CIA activities within the United States disclosed for the first time that in 1953 an Army scientist had fallen to his death from a hotel room in New York after the CIA had given him LSD.

The Olson family confronted Ruwet, who confirmed that the scientist was Frank Olson. The family demanded a full accounting, assurances from the government that such experiments would never again be permitted, and a financial settlement.

In the White House, then-Deputy Chief of Staff Dick Cheney wrote a memo to Chief of Staff Donald Rumsfeld on "The Olson Matter/CIA Suicide."

Cheney wrote that there were "serious legal questions that [would] have to be resolved concerning the Government's responsibility," and expressed concern that it "might be necessary to disclose high-level classified national security information in connection with any court suit."

Ford invited the Olsons to the Oval Office, where he apologized for Olson's death. The family agreed to a $750,000 settlement, approved by Congress in legislation sponsored by Mathias.