On April 19, 1968, Sarti was arrested along with fellow Corsicans Auguste Joseph Ricord and Francois Chiappe for questioning regarding the robbery of a branch of the National Bank of Argentina. The three were released due to lack of evidence. In April 1972, Sarti was shot to death in Mexico City during a police raid of a drug trafficking ring. A detective in Rio de Janeiro was later suspended from the police force after being accused of accepting a bribe to free Sarti and Helena Ferreira, his girlfriend, from jail earlier in 1972.
Allegations of involvement in the assassination of John F. Kennedy
The Men Who Killed Kennedy
On October 25, 1988, the British television program The Men Who Killed Kennedy named Sarti as one of three French gangsters involved in the assassination of John F. Kennedy. According to the program, Sarti, Roger Bocagnani, and Sauveur Pironti were contracted by organized crime in the United States. In the French newspaper Le Provençal published the following day, Pironti denied the allegation stating he believed at the time of the assassination that Sarti was held in Marseille's Baumettes Prison and that Bocagnani was in Bordeaux's Fort du Hâ. He also showed the paper military records showing that he was serving on a minesweeper from October 1962 to April 1964. The French Ministry of Justice stated that Bocagnani was in prison on the day of Kennedy's assassination and officials for the French Navy confirmed Pironti's military service. Pironti's assertion that Sarti was in prison has not been confirmed.
E. Howard Hunt
After the death of career CIA operative, spy novelist and convicted Watergate burglar E. Howard Hunt in 2007, Saint John Hunt and David Hunt stated that their father had recorded several claims about himself and others being involved in a conspiracy to assassinate John F. Kennedy. In the April 5, 2007 issue of Rolling Stone, Saint John Hunt detailed a number of individuals purported to be implicated by his father including an assassin he termed "French gunman grassy knoll"  who many presume was Sarti, as well as Lyndon B. Johnson, Cord Meyer, David Phillips, Frank Sturgis, David Morales, and William Harvey.
In his book "Bond of Secrecy" Saint John Hunt relates that his father remembered the name of a French gunman firing from the grassy knoll "sounded something like Sarte or Satre".  The case against Sarti originally stemmed from the British television series referenced above, in which researcher Steve Rivele interviewed imprisoned Corsican drug smuggler Christian David, eventually to be given a single name "Lucien". After further inquiries, Rivele himself supposed that Lucien was Lucien Sarti which David then confirmed. However assassination researchers have also implicated another French heroin smuggler and assassin using the possible pseudonym of Michel Mertz as well as his real name Jean Souetre, and with much stronger evidence.
Souetre appears in CIA  and FBI  documents released in 1977 under the Freedom of Information Act as having been in the Dallas area around the time of the assassination and actually in Dallas on November 22, 1963. He had previously been a commando in the French foreign legion stationed in Algeria. According to his military record  he was arrested for desertion after joining the OAS (Secret Army Organization), a resistance movement opposed to Algerian independence from France, which orchestrated numerous failed assassination plots against President DeGaulle. In 1962 Souetre escaped from a detention camp at Saint Maurice l'Ardoise. Following another failed OAS assassination attempt, he was sentenced to death in absentia. However still according to the record, Souetre was in Algeria and then the African sub-continent fighting as a mercenary from early 1962 until 1968 when he was repatriated to France.
Souetre himself later claimed he was not in Dallas, but that still another heroin dealer named Michel Mertz was using his name as a pseudonym. However the documents referenced above actually have it the other way around. They list Michel Mertz as one of Souetre's pseudonyms. While it's possible that both used the other's name on occasion, and that the CIA and the FBI had the names confused, there seem to be no official documents related to a Michel Mertz.
Indeed, one of the FBI documents referenced above is a memo from the CIA to the FBI about Souetre indicating that he himself disclosed that he traveled on various passports, one being a U.S. passport. The memo concerns a meeting in Portugal between Souetre and CIA representatives where he asked for help for the OAS, who were then being hunted by French authorities. A close reading of more of these documents reveals some inconsistencies as to the identity of certain French visitors who were in and around Dallas in November 1963 and who left shortly after the assassination. It appears that the FBI suspected and investigated a sophisticated effort at concealment including the use of pseudonyms. Some sections are redacted.
In 2009 San Francisco attorney Anthony Bothwell requested the CIA release any additional information it has on Jean Souetre. The CIA responded that any records on Souetre would be exempt from the Freedom of Information Act as "intelligence sources and methods information". In 2013 Bothwell filed a federal lawsuit demanding a court order forcing the CIA to produce whatever records it has on Jean Souetre.
The above information doesn't exonerate Sarti, but there is no known record of his presence in Dallas as there is of Souetre's. However it can be supposed he would have been using a pseudonym. Furthermore, it seems entirely possible that E. Howard Hunt wasn't sure of the name he remembered, but remembered that it sounded like Sarte or Satre, because he actually heard two different but similar-sounding French names being variously mispronounced.
Whoever the "French gunman" was, Hunt's claims of a high level Johnson-CIA conspiracy would have been difficult to prove and the two sons alleged that their father cut the information from his memoirs, "American Spy: My Secret History in the CIA, Watergate and Beyond", to avoid possible perjury charges. According to Hunt's widow and other children, the two sons took advantage of Hunt's loss of lucidity by coaching and exploiting him for financial gain. The Los Angeles Times said they examined the materials offered by the sons to support the story and found them to be "inconclusive".
An insider's account of Lyndon Johnson's rise to power and the corrupt Texas politics of the time can be found in the autobiographical book "Billy Sol Estes: A Texas Legend", now apparently out of print but available online.  This book discusses the testimony Estes provided to a Texas Grand Jury naming Johnson as complicit in several murders, one being that of John F. Kennedy. It also contains alleged details of the assassination plot, including the strategy of planting numerous false leads and a reference to the French Connection. Estes also remembered hearing some French names. Another insider Madeleine Brown, who claims to have been Johnson's mistress, has stated that Johnson laid blame for Kennedy's death on "the oil men and the intelligence men".
The following is editorial commentary by this author. It should be remembered that Johnson and his supporters were Roosevelt era New Deal Democrats, that the Kennedy brothers were virulent anti-communists, and that the oil men and the intelligence men were the tactical heroes of World War II. Such circumstances may be why those in the know are still reluctant to press charges, even for the sake of history. Maybe it's just that it turned out they were, shall we say misinformed, and that President Kennedy was right. Moreover, the matter of full culpability may still be unsettled, as Johnson himself indicated in a 1969 interview with Walter Cronkite that wasn't finally broadcast until 1975, on the basis of national security.
There were 100 tactical nuclear weapons in Cuba after the Cuban missile crisis  which had been undetected by U.S. aerial reconnaissance flights, and which were not revealed to Kennedy by Russian Premier Nikita Khrushchev during negotiations to have the medium range ballistic missiles removed. These weapons were Hiroshima-sized warheads fitted to cruise missiles, artillery fired shells and airborne bombs. The last could have been delivered to U.S. cities in the Southeast using Soviet made IL-28 bombers in the possession of the Cuban regime. Secretary of Defense Robert McNamara lobbied Kennedy to also have these bombers removed some weeks after the missiles. The still undiscovered warheads were unilaterally withdrawn by Khrushchev within a few months, because he felt Castro was unstable, having already made threats. 
During the Cuban Missile Crisis itself, CIA counterintelligence specialist William Harvey organized unauthorized reconnaissance missions into Cuba.  On November 5, 1962 Cuban officials arrested the leader of these missions who then provided information about CIA operations on the island.  President Kennedy reacted to what could have been provocatory to a nuclear confrontation he was trying to defuse through negotations, by having Harvey exiled to a post in Rome, where his CIA career ended. Later during the summer of 1963, self-described Cuban freedom fighter Loran Hall would make a series of speeches at meetings of the John Birch Society describing unauthorized commando raids he'd participated in. On a recording of one such speech, which he had pressed into a vinyl record for promotional sale, he tells of smuggling photos out of Cuba containing evidence of what sounds like the airborne nuclear bombs, among other Russian-made weaponry and aircraft, at San Antonio de los Banos airbase. He passionately decries how the existence of these photos was suppressed and possibly leaked. 
In the winter of 1963 the CIA received an anecdotal report that some warheads and missiles remained in Cuba. However the agreement Kennedy had made with Khrushchev didn't allow for on site inspections. An unauthorized mission to verify this information included a photographer from Life Magazine, whose role was to obtain evidence for national publication, that Kennedy had fallen prey to Soviet deception or worse. The mission failed and men were lost.   There were in fact no more nuclear weapons in Cuba well before assassination plans went into effect. However the threat of nuclear war, much like a gun to the head, tends to focus the attention of anyone to whom it is directed. In this instance the potential for a nuclear response to covert aggression may have also united otherwise disparate elements in a common cause.
Within five years and in the cold light of internationalist politics The Establishment decided they had simply made an error in judgement by trusting Lyndon Johnson. But then Kennedy's brother Robert was also assassinated while campaigning for the presidential office Johnson voluntarily vacated. Within twelve years of John F. Kennedy's murder there were shakeups at many levels of the U.S. Government especially the CIA and the Executive Branch. A third brother of the slain president, Edward Kennedy maintained a powerful seat in the U.S. Senate for the remainder of his natural life.
- Davis, John H. Mafia Kingfish: Carlos Marcello and the Assassination of John F. Kennedy. New York: Signet, 1989. ISBN 0-451-16418-0
- Kruger, Henrik. The Great Heroin Coup: Drugs, Intelligence, and International Fascism. Boston: South End Press, 1980. ISBN 0-89608-031-5
- Marrs, Jim. Crossfire: The Plot That Killed Kennedy. New York: Carroll & Graf, 1990. ISBN 0-88184-648-1
- Mills, James. The Underground Empire: Where Crime and Governments Embrace. Garden City NY: Doubleday, 1986. ISBN 0-385-17535-3
- Scott, Peter Dale and Marshall, Jonathan. Cocaine Politics: Drugs, Armies, and the CIA in Central America. Berkeley: University of California Press, 1991. ISBN 0-520-07312-6
- Sterling, Claire. Octopus: The Long Reach of the International Sicilian Mafia. New York: Simon & Schuster (Touchstone Edition), 1991. ISBN 0-671-73402-4
- Clark, Evert and Nicholas Horrock (1973). Contrabandista! Praeger, ASIN B0006C4TXQ. The authors state Sarti was 41 at time of death.
- Menéndez, Jorge Fernández (November 22, 2013). "Kennedy: Oswald, Sarti, México". Excélsior. Mexico City. Retrieved November 9, 2014.
- "The dice turn sour for a pair of high rollers". The Gazette. Montreal. February 8, 1975. p. 12. Retrieved December 8, 2014.
- Hall, Isabelle (September 22, 1972). "Heroin, Smuggling Case May Uncover Mystery". Ludington Daily News. Ludington, Michigan. UPI. p. 8. Retrieved December 8, 2014.
- "Jail Escape Plot, Rio Cop Linked". The Pittsburgh Press. Pittsburgh, Pennsylvania. UPI. November 15, 1972. p. 36. Retrieved December 8, 2014.
- "French accused of killing JFK". Observer-Reporter. Washington, PA. AP. October 27, 1988. p. A-8. Retrieved March 4, 2013.
- Williams, Carol J. (March 20, 2007). "Watergate plotter may have a last tale". Los Angeles Times. Los Angeles. Retrieved December 30, 2012.
- Hedegaard, Erik (April 5, 2007). "The Last Confessions of E. Howard Hunt". Rolling Stone. Archived from the original on June 18, 2008.
- McAdams, John (2011). "Too Much Evidence of Conspiracy". JFK Assassination Logic: How to Think About Claims of Conspiracy. Washington, D.C.: Potomac Books. p. 189. ISBN 9781597974899. Retrieved December 30, 2012.
- Hunt, Saint John (2008). "Secrets Revealed". Bond of Secrecy. Walterville, OR: Trine Day LLC. p. 54.
- The Men Who Killed Kennedy - an article on the TV series, which mentions David's claim of Sarti's involvement.