WASHINGTON -- Nearly 60 years after the death of a government scientist who had been given LSD by the Central Intelligence Agency without his knowledge, his family says it plans to sue the government, alleging that he was murdered and did not commit suicide as the C.I.A. has long maintained.
Eric and Nils Olson, whose father, Frank Olson, was the scientist, said they plan to file a lawsuit in United States District Court here on Wednesday accusing the C.I.A. of covering up the truth about Mr. Olson's death in 1953, one of the most infamous cases in the agency's history.
During the intelligence reforms in the 1970s, the government gave the Olson family a financial settlement after the C.I.A. was forced to acknowledge that Mr. Olson had been given the hallucinogenic drug nine days before his death. President Gerald R. Ford met with the Olson family at the White House and apologized.
At the time, the government said Mr. Olson had killed himself by jumping out of a hotel window in Manhattan. But the Olsons came to believe that he had been murdered to keep him from talking about disturbing C.I.A. operations that he had uncovered.
Mr. Olson's sons said that their past efforts to persuade the agency to open its files and provide them with more information had failed, and that a court challenge is the only way to find out the truth.
"The evidence points to a murder, and not a drug-induced suicide," said Eric Olson, Frank Olson's older son, who has devoted much of his life to investigating his father's death. When the government told his family that his father had committed suicide, "one set of lies was replaced with another set of lies," he said.
Jennifer Youngblood, a C.I.A. spokeswoman, said the agency does not comment on pending court cases, but she noted that the C.I.A.'s most controversial episodes from the early cold war years, like Mr. Olson's death, "have been thoroughly investigated over the years, and the agency cooperated with each of those investigations."
The Olson case was one of the most explosive revelations about the C.I.A. during the post-Watergate investigations of the United States intelligence community in the mid-1970s, and was part of a series of disclosures about a C.I.A. program known as MK-Ultra, which included brainwashing, mind control and other human behavioral control experiments during the early days of the cold war.
Over the decades, the Olson case has gained a kind of pop culture status as one of the signature examples of government secrecy and abuse, and references to the death have been made in television, film, books and music.
"The C.I.A.'s wrongful conduct in this case continues under the present administration," said Scott Gilbert, a Washington lawyer representing the Olson brothers. "I have met personally with senior agency officials who still refuse to acknowledge the truth and to provide us with all documents relevant to this matter."
Frank Olson was a bioweapons expert working at the special operations division of the Army's Biological Laboratory at Fort Detrick in Maryland. The C.I.A. worked jointly with the special operations division, researching biological agents and toxic substances.
In 1953, Mr. Olson traveled to Europe and visited biological and chemical weapons research facilities. The Olson family lawsuit alleges that during that trip, Mr. Olson witnessed extreme interrogations, some resulting in deaths, in which the C.I.A. experimented with biological agents that he had helped develop. Intelligence officials became suspicious of him when he seemed to have misgivings about what he had seen, the lawsuit contends. Eric Olson said Frank Olson also appeared to have deep misgivings about the use of biological weapons that was alleged in the Korean War.
A few months later, he attended a meeting with officials from both the special operations division and the C.I.A. at Deep Creek Lake, Md. Sometime during the meeting on Nov. 19, 1953, he was given a drink of Cointreau that had been secretly spiked with LSD by C.I.A. officials.
Mr. Olson returned home, and over the following weekend told his wife that he wanted to leave his job. Eric Olson said his mother later recalled that Frank Olson did not seem suicidal or psychotic that weekend, but was reflective about his work.
On Nov. 24, Mr. Olson told a colleague that he wanted to resign, according to the lawsuit. Instead, he and several C.I.A. officials traveled to New York, supposedly for a psychiatric evaluation. On Nov. 28, Mr. Olson fell to his death from his room in the Statler Hotel. His sons now express skepticism about the government's official story that he had committed suicide because he was given LSD more than a week earlier.
In the 1990s, the family had Mr. Olson's body exhumed and an autopsy performed, and the New York district attorney's office later conducted an inconclusive investigation into the death.
Eric Olson says that his father's death and its aftermath had devastating consequences for his family. He said his mother, who is now dead, suffered from alcoholism. "We want justice," Mr. Olson said. "This has cost me an immense amount of time and years of my life."
This article originally appeared in The New York Times.