American filmmaker Oliver Stone said Tuesday that the assassination of former President John F. Kennedy is “a cold case with a lot of clues” after he testified before Congress earlier in the day.

Oliver Stone urged lawmakers in Washington, D.C, Tuesday to reopen the investigation into the assassination of President John F. Kennedy, who was killed Nov. 22, 1963.

So what did the witnesses tell lawmakers? Testimony from Stone and authors Jefferson Morley and James DiEugenio largely centered around criticism of the CIA and other federal officials in the decades since Kennedy's assassination.