Los Angeles (CNN) -- A controversial assertion by convicted Robert F. Kennedy assassin Sirhan Sirhan to win his freedom was challenged this week by the California attorney general who said "overwhelming evidence" exists against Sirhan's claims. Sirhan's attorneys have said that a second gunman actually assassinated Kennedy in 1968 and that Sirhan was hypno-programmed to fire a gun as a diversion. "In sum, (Sirhan) cannot possibly show that no reasonable juror would have convicted him if a jury had considered his 'new' evidence and allegations, in light of the overwhelming evidence supporting the convictions and the available evidence thoroughly debunking (Sirhan's) second-shooter and automaton theories," Attorney General Kamala Harris said in federal court papers filed this week.
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Convicted assassin Sirhan Sirhan asserts a second gunman killed Robert F. Kennedy
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Sirhan was hypno-programmed to fire a gun as a diversion, his attorney says
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California's attorney general says a jury would have convicted him anyway
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The evidence against Sirhan is "overwhelming," prosecutor says
She said that under @placeholder's vicarious liability law, "an aider and abettor 'is guilty not only of the offense he intended to facilitate or encourage, but also of any reasonably foreseeable offense committed by the person he aids and abets'."