Sirhan Sirhan, the assassin of Democratic presidential candidate Robert Kennedy in 1968, faces a California parole board for the 15th time on Wednesday.

Sirhan, 71, will have a suitability hearing at Richard J. Donovan Correctional Facility near San Diego, the California Board of Parole Hearings said on its website.

The Palestinian-born Sirhan is serving a life sentence for gunning down Kennedy at the Ambassador Hotel in Los Angeles, shortly after he won the California Democratic presidential primary. Kennedy died the next day.

Sirhan was sentenced to death in 1969. His sentence was commuted to life in prison after California banned the death penalty.

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He has said that he had no recollection of the killing and also that he had fired at Kennedybecause he was enraged by his support for Israel.

Sirhan was last denied parole in 2011 and is being housed in a state prison in San Diego.

Sirhan's lawyers failed last year to persuade a U.S. District judge to free him because he was innocent.

Defense lawyers had argued that Sirhan had not been physically in position to fire the fatal shot, and that a second shooter and gun may have been responsible.

Kennedy was a U.S. senator from New York when he died at age 42. His older brother, President John F. Kennedy, was assassinated in 1963.