Sirhan was born in Jerusalem in Mandatory Palestine to a Christian family of Greek Orthodox background, although he attended a Lutheran school and is a strong opponent of Israel. In 1989, he told David Frost, "My only connection with Robert Kennedy was his sole support of Israel and his deliberate attempt to send those 50 bombers to Israel to obviously do harm to the Palestinians." Some scholars believe that the assassination was the first major incident of political violence in the United States stemming from the Arab–Israeli conflict in the Middle East.
Sirhan was born into an Arab Palestinian family in Jerusalem, Mandatory Palestine. When he was 12 years old his family emigrated, moving briefly to New York and then to California. In Altadena, he attended Eliot Junior High School, followed by John Muir High School and Pasadena City College, both in Pasadena. Sirhan's father, Bishara, was characterized as a stern man who often beat his sons harshly. Shortly after the family's move to California, Bishara returned alone to the Middle East. Sirhan never became an American citizen, retaining instead his Jordanian citizenship.
As an adult, Sirhan changed church denominations several times, joining Baptist and Seventh-day Adventist churches. Then in 1966, he joined the occult organization Ancient Mystical Order of the Rose Cross, commonly known as Rosicrucians.
Around 12:15 a.m. PDT on June 5, 1968, Sirhan fired a .22 caliber Iver-Johnson Cadet revolver at Senator Robert Kennedy and the crowd surrounding him in the Ambassador Hotel in Los Angeles shortly after Kennedy had finished addressing supporters in the hotel's main ballroom. Authors George Plimpton and Pete Hamill, football Hall of Famer Rosey Grier, and 1960 Olympic gold medalist Rafer Johnson were among several men who subdued and disarmed Sirhan after a lengthy struggle.
Kennedy was shot three times, once in the head and twice in the back, with a fourth bullet passing through his jacket. He died nearly 26 hours later. Five other people at the party were also shot, but all five recovered: Paul Schrade, an official with the United Automobile Workers union; William Weisel, an ABC TV unit manager; Ira Goldstein, a reporter with the Continental News Service; Elizabeth Evans, a friend of Pierre Salinger, one of Kennedy's campaign aides; and Irwin Stroll, a teenage Kennedy volunteer.
Despite Sirhan's admission of guilt, recorded in a confession made while in police custody on June 9, a lengthy trial followed. The court judge did not accept his confession and denied his request to withdraw his not guilty plea so that he could plead guilty.
On February 10, 1969, Sirhan's lawyers made a motion in chambers to enter a plea of guilty to first-degree murder in exchange for life imprisonment (rather than the death penalty). Sirhan announced to the court judge, Herbert V. Walker, that he wanted to withdraw his original plea of not guilty in order to plead guilty as charged on all counts. He also asked that his counsel "dissociate themselves from this case completely." When the judge asked him what he wanted to do about sentencing, Sirhan replied, "I will ask to be executed."
Judge Walker denied the motion and stated, "This court will not accept the plea." The judge also denied Sirhan's request for his counsel to withdraw; when his counsel entered another motion to withdraw from the case of their own volition, Walker denied this motion as well. Judge Walker subsequently ordered that the record pertaining to the motion be sealed.
The trial proceeded, and opening statements began on February 12. The lead prosecutor in the Sirhan case was Lynn "Buck" Compton, a World War II veteran of Easy Company fame who later became a justice on the California Court of Appeal. The prosecution's opening statement, delivered by David Fitts, was replete with examples of Sirhan's deliberate preparations to kill Kennedy. The prosecution was able to show that just two nights before the attack, on June 3, Sirhan was seen at the Ambassador Hotel, apparently attempting to learn the building's layout; evidence proved that he visited a gun range on June 4. Further testimony by Alvin Clark seemed especially damning. Clark, Sirhan's garbage collector, claimed that Sirhan had told him a month before the attack of his intention to shoot Kennedy.
Sirhan's defense counsel, which included attorney Grant Cooper, had hoped to demonstrate that the killing had been an impulsive act of a man with a mental deficiency, but when Judge Walker admitted into evidence pages from three of the journal notebooks that Sirhan had kept, it was clear that the murder was not only premeditated, but also "quite calculating and willful."
On March 3, 1969, in the Los Angeles courtroom, Cooper asked Sirhan directly in testimony if he had indeed shot Senator Kennedy. Sirhan replied immediately: "Yes, sir," but then stated that he did not bear any ill-will towards Kennedy. Sirhan also testified that he had killed Kennedy "with 20 years of malice aforethought." He explained in an interview with David Frost in 1989 that this referred to the time since the creation of the State of Israel. He has maintained since then that he has no memory of the crime, nor of making that statement in open court.
During Sirhan's testimony, Cooper asked him to explain his reasons for the attack on Kennedy. Sirhan launched into "a vicious diatribe about the Middle East conflict between Arab and Jew." Defense counsel Emile Zola Berman, who was Jewish, was upset by Sirhan's statements and expressed his intentions to resign from the defense team. Berman was eventually talked out of resigning by Cooper and stayed until the end of the trial.
During the trial, the defense primarily based their case on the expert testimony of Bernard L. Diamond, M.D., a professor of law and psychiatry at University of California, Berkeley, who testified that Sirhan was suffering from diminished capacity at the time of the murder. Sirhan's behavior throughout the trial was indeed bizarre, and at one point, he became outraged during testimony about his childhood.
Sirhan was convicted on April 17, 1969, and was sentenced six days later to death in the gas chamber. Three years later, his sentence was commuted to life in prison, owing to the California Supreme Court's decision in The People of the State of California v. Robert Page Anderson, 493 P.2d 880, 6 Cal. 3d 628 (Cal. 1972), which ruled capital punishment a violation of the California Constitution's prohibition of cruel and unusual punishment. The California Supreme Court declared in the Anderson case that its decision was retroactive, thereby invalidating all prior death sentences imposed in California.
Sirhan's lawyer Lawrence Teeter later argued that Grant Cooper was compromised by a conflict of interest and was, as a consequence, grossly negligent in defense of his client. The defense moved for a new trial amid claims of set-ups, police bungles, hypnotism, brainwashing, blackmail, and government conspiracies. On June 5, 2003, coincidentally the 35th anniversary of Kennedy's assassination, Teeter petitioned a federal court in Los Angeles to move the case to Fresno. He argued that Sirhan could not get a fair hearing in Los Angeles, where a man who helped prosecute him is now a federal judge: U.S. District Judge William Matthew Byrne, Jr. in Los Angeles was a deputy U.S. attorney during Sirhan's trial, and part of the prosecutorial team. Teeter had been trying since 1994 to have state and federal courts overturn the conviction, arguing that his client was hypnotized and framed, possibly by a government conspiracy. He was granted a June 30 hearing. During the hearing, Teeter referred to testimony from the original trial transcripts regarding a prosecution eyewitness to the attack, author George Plimpton, in which he said that Sirhan looked "enormously composed. He seemed... purged." This statement coincided with the defense's argument that Sirhan had shot Kennedy while in some kind of hypnotic trance. The motion was denied. Teeter died in 2005, and Sirhan declined other counsel to replace him.
On November 26, 2011, Sirhan's defense teams filed new court papers for a new trial, saying that "expert analysis of recently uncovered evidence shows two guns were fired in the assassination and that Sirhan's revolver was not the gun that shot Kennedy" and he "should be freed from prison or granted a new trial based on 'formidable evidence', asserting his innocence and 'horrendous violations' of his rights."
On January 5, 2015, Sirhan was denied freedom by U.S. District Judge Beverly Reid O'Connell in Los Angeles, who said that Sirhan "failed to meet the showing required for actual innocence" that might excuse his having failed to seek his freedom sooner in federal court. Sirhan's case was not strong enough. "Though petitioner advances a number of theories regarding the events of June 5, 1968, petitioner does not dispute that he fired eight rounds of gunfire in the kitchen pantry of the Ambassador Hotel," O'Connell wrote. "Petitioner does not show that it is more likely than not that no juror, acting reasonably, would have found him guilty beyond a reasonable doubt."
A motive cited for his actions is the Middle East conflict. After his arrest, Sirhan said, "I can explain it. I did it for my country." Sirhan believed that he was deliberately betrayed by Kennedy's support for Israel in the June 1967 Six-Day War, which had begun exactly one year to the day before the assassination. During a search of Sirhan's apartment after his arrest, a spiral-bound notebook was found containing a diary entry which demonstrated that his anger had gradually fixated on Robert Kennedy, who had promised to send 50 fighter jets to Israel if he were elected president. Sirhan's journal entry of May 18, 1968, read: "My determination to eliminate R.F.K. is becoming the more and more of an unshakable obsession...Kennedy must die before June 5th." They found other notebooks and diary entries which contained his growing rage at Zionists, particularly at Kennedy; his journals also contained many nonsensical scribbles, which were thought to be his version of "free writing."
The next day, on June 6, the Los Angeles Times printed an article by Jerry Cohen which discussed Sirhan's motive for the assassination, confirmed by the memos that Sirhan wrote to himself. The article stated:
When the Jordanian nationalist, Sirhan Bishara Sirhan, allegedly shot Kennedy, ostensibly because of the senator's advocacy of U.S. support for Israel, the crime with which he was charged was in essence another manifestation of the centuries-old hatred between Arab and Jew.
M.T. Mehdi, then secretary-general of the Action Committee on American-Arab Relations, believed that Sirhan had acted in justifiable self-defense, stating: "Sirhan was defending himself against those 50 Phantom jets Kennedy was sending to Israel." Mehdi wrote a 100-page book on the subject called Kennedy and Sirhan: Why?
Later in prison, Sirhan claimed that he was drunk. An interview with Sirhan in 1980 revealed new claims that a combination of liquor and anger over the anniversary of the 1967 Arab-Israeli war triggered his actions the night when he assassinated Kennedy. "You must remember the circumstances of that night, June 5. That was when I was provoked," Sirhan says, recorded in a transcript of one of his interviews with Mehdi, later president of the New York-based American-Arab Relations Committee. "That is when I initially went to observe the Jewish Zionist parade in celebration of the June 5, 1967, victory over the Arabs. That was the catalyst that triggered me on that night." Then Sirhan said, "In addition, there was the consumption of the liquor, and I want the public to understand that."
In 1971, Sirhan was housed in the Adjustment Center at San Quentin State Prison. He was subsequently transferred to the Correctional Training Facility (CTF) in Soledad, California, where he was confined until 1992. From 1992 to 2009, he was confined at the California State Prison (COR) in Corcoran, California, and lived in COR's Protective Housing Unit until he was moved to a harsher lockdown at COR in 2003. In October 2009, ostensibly for his own safety, he was transferred to the Pleasant Valley State Prison in Coalinga, California, where he was housed in a cell by himself. He was subsequently moved back to Corcoran.
On November 22, 2013, Sirhan was transferred from Corcoran to the Richard J. Donovan Correctional Facility in San Diego County. The transfer occurred on the 50th anniversary of the assassination of President John F. Kennedy, but a spokesman for the California Department of Corrections and Rehabilitation said that the transfer was "a routine matter of housing allotments" and its timing was "simply an unfortunate coincidence."
In a 1980 interview with M.T. Mehdi, Sirhan claimed that his actions were fueled by liquor and anger. He then complained that the parole board was not taking these "mitigating" circumstances into account when they continually denied his parole.
On May 10, 1982, Sirhan told the parole board: "I sincerely believe that if Robert Kennedy were alive today, I believe he would not countenance singling me out for this kind of treatment. I think he would be among the first to say that, however horrible the deed I committed 14 years ago was, that it should not be the cause for denying me equal treatment under the laws of this country."
A parole hearing for Sirhan is now scheduled every five years.
On March 2, 2011, after 42 years in prison, Sirhan's 14th parole hearing was held, with Sirhan represented by his current attorney, William Francis Pepper. At this parole hearing, Sirhan testified that he continues to have no memory of the assassination nor of any details of his 1969 trial and confession. Pepper also repeated the claim, which Sirhan's lawyers had previously stated, that Sirhan was "hypno programmed" and his memory of being programmed was "wiped" by an unknown conspiracy behind the assassination which is why Sirhan has no recall of the murder. Pepper said he hired Dr. Daniel Brown of Harvard Medical School to spend more than sixty hours with Sirhan Sirhan in prison and recover his memory of both the shooting and having been put under hypnosis. His parole was denied on the grounds that Sirhan still does not understand the full ramifications of his crime.
On February 10, 2016, at his fifteenth parole hearing, Sirhan was denied parole again in a federal courthouse in San Diego. One of Sirhan's shooting victims from that night, Paul Schrade, now aged 91, testified in support of Sirhan, stating his belief that a second shooter killed Robert Kennedy and that Sirhan was intended to be a distraction from the real gunman by an unknown conspiracy who plotted to kill Kennedy. Sirhan also repeated his story in claiming to have no memory of the shooting of Kennedy at the Ambassador Hotel. In his testimony before the parole board, Sirhan recalled events before the shooting in some detail – going to a shooting range the day before, June 4, 1968, visiting the hotel on June 5 in search of a party and returning to the lobby after realizing he had drunk too many Tom Collins cocktails to drive. He next claimed to have drunk coffee in a backstage area near the hotel pantry with a woman to whom he was attracted, and who may have been involved with the conspiracy to assassinate Kennedy. Dr. Brown has stated that the unknown woman then took Sirhan into the pantry, which Sirhan described in his prison memory sessions as a dark room at the hotel, and that while in the pantry the woman gave Sirhan a post-hypnotic cue to fire a gun in the direction of Robert Kennedy minutes later. Sirhan was immediately subdued by several men in the pantry as Kennedy fell to the pantry floor fatally wounded. Sirhan has claimed that after having coffee with the woman, the next thing his conscious memory can remember is his being choked and unable to breathe moments after the Kennedy shooting, stating: "It's all vague now. I'm sure you all have it in your records. I can't deny it or confirm it. I just wish this whole thing had never taken place."
Sirhan's next parole hearing will be in 2021.