SIRHAN B. SIRHAN WAS THE ONLY PERSON TO ASSASSINATE RFK
That argument is not only oversimplified it is an impossible conclusion based on forensic findings. If you recall RFK, Robert Francis Kennedy, aka Bobby Kennedy was the front-runner for the Democratic nomination for President of the United States. In fact, his poll numbers showed him as the clear leader, and the numbers were off the charts. Furthermore, his overall popularity would have made it certain RFK would defeat any Republican challenger, including Richard Milhouse Nixon, who became President in 1968.
 

In 1968, I| months after announcing his bid for the office of POTUS Bobby Kennedy was killed in the kitchen of the Ambassador hotel, Los Angeles, California. He was 42 years of age. His security detail dispatched at the hotel were current football players from the Los Angeles Rams. RFK had been denied Secret Service protection under President Lyndon Johnson who could have authorized the Secret Service protection but did not.
 

RFK had iust delivered a speech after winning the California and North Dakota primaries on June 5, 1968 to an enthusiastic crowd in the Ambassador Ballroom and was departing the venue taking a route through the kitchen. The gun shots rang out and, as witnesses described, there were more than 8 shots heard in the kitchen. The accused and convicted assassin Sirhan Sirhan had fired all 8 shots from a 22caliber revolver. All eight shell casings remained in the weapon because shell casings always remain in a revolver and are not ejected as in a semi-automatic weapon. During the shooting he wounded five others for a total of 6 people shot. Police recovered 7 shots from the bodies of the six victims. How could he shoot 6 people total of 7 wounds if three bullets hit RFK and Sirhan only had 8 shots in the revolver? 
 

The case for only one assassin unravels very quickly. RFK was actually shot in three areas of his body. The left side near the neck, the upper left side of the chest and the back of the right side of his head behind the right ear. Bone and bullet fragments were embedded in the brain, with extensive damage to the right cerebellum and right occipital cortex. RFK died of massive damage to his brain. Based on bullet trajectories how could FK been shot behind the ear by Sirhan Sirhan because Sirhan was directly in front of RFK the entire time. In addition, there were powder burns behind the back of the ear indicating close range. Sirhan was tackled to the ground by Rosie Greer of the Los Angeles Rams and Sirhan was clearly in front of RFK.

Interesting and suspicious that a bullet fragment test was never conduced in either case of Bobby F Kennedy or John F Kennedy assassinations. These tests were available through the FBI laboratory in |968. These would have revealed if the shell casings matched up with the bullet fragments/projectiles.
 

Sirhan did not kill RFK he wounded him but did not succeed in making the 'kill shot FK was shot in the back of the head with a briefcase gun, a hand gun hidden inside the briefcase. Using this device, witnesses would not be able to see if another shooter was involved. In addition, the shell casings would remain inside the case and would not be recoverable by law enforcement investigators.
See exhibit A. photo

The real assassin was working as a contract killer for the United States Central Intelligence Agency and hired under the disgraced Deputy Director Charles Cabell formerly of the CIA forced to resign on November 29, 1961 for the illegal Cuban 'Bay of Pigs" Invasion and other CIA illegal activities conducted overseas. Also forced to resign was Allen Dulles acting CIA director. He was forced to resign under the orders of President JFK.  Cabell holding this grudge against President Kennedy, ordered the hit on JFK in tandem with Allan Dulles working with Fidel Castro hiring Lee Harvey Oswald to also attempt to assassinate JFK. 
 

Oswald never made the actual kill shot on JFK but Charles Cabell's man, perched at the railroad tracks located in front of Daley Plaza, Dallas, Texas finished the job with a head shot on JFK.
 

The Warren Commission led by the Johnson Administration and Dallas police force, covered up the real reasons and those actually behind the assassination of JFK. But had RFK become President, RFK as POTUS would be searching FBI and CIA files that would lead him to the truth and to who exactly was behind the murder of his brother. For that reason, Bobby Kennedy had to be eliminated. 
 

To make matters more complex, Sirhan B. Sirhan was a victim of hypnosis and psychological programming by the CIA directed to assassinate RFK. To this day after being interviewed by thousands of professionals including a in-person visit at the prison housing Sirhan, by RFK Jr. Sirhan cannot remember a single detail of the attack on Bobby Kennedy.