Yes, here is the man that these powerful conspirators were so afraid would expose their conspiracy that they had him killed.
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Dozens of reporters, live cameras. This is how they "silenced" him. But this was done to give Ruby a chance to shoot him. So why didn't Ruby do it? Never mind.
They gave Oswald numerous opportunities to expose their conspiracy; but he never did. He talked to his family, to the head of the Dallas Bar, to numerous reporters. But not a word from him about this conspiracy.
To normal people that's evidence that there wasn't one. To conspiracy thinkers it's evidence that there was.