Robert F. Kennedy Jr. is convinced that a lone gunman wasnt solely responsible for the assassination of his uncle, President John F. Kennedy. Kennedy and his sister, Rory, spoke about their family [on January 11] while being interviewed in front of an audience ... in Dallas. The event comes as a year of observances begins for the 50th anniversary of the presidents death. Their uncle was killed on Nov. 22, 1963, while riding in a motorcade through Dallas. Five years later, their father was assassinated in a Los Angeles hotel while celebrating his win in the California Democratic presidential primary. Robert F. Kennedy Jr. said his father spent a year trying to come to grips with his brothers death, reading the work of Greek philosophers, Catholic scholars, Henry David Thoreau, poets and others trying to figure out ... the existential implications of why a just God would allow injustice to happen of the magnitude he was seeing. He said his father thought the Warren Commission, which concluded Lee Harvey Oswald acted alone in killing the president, was a shoddy piece of craftsmanship. He said that he, too, questioned the report. The evidence at this point I think is very, very convincing that it was not a lone gunman, he said, but he didnt say what he believed may have happened. He said his father had investigators do research into the assassination and found that phone records of Oswald and nightclub owner Jack Ruby, who killed Oswald two days after the presidents assassination, were like an inventory of mafia leaders the government had been investigating. He said his father, later elected U.S. senator in New York, was fairly convinced that others were involved.