Cooper declared the men "innocent of these charges" Wednesday and accused Durham District Attorney Mike Nifong of "overreaching," the Raleigh News & Observer reported.
"This case shows the enormous consequences of over-reaching by a prosecutor," Cooper said at a news conference. "The Durham District Attorney pushed forward unchecked. There were many moments in this case where caution would have served better than bravado."
Cooper said the charges were the result of "a tragic rush to accuse and a failure to verify serious allegations."
The newspaper said Nifong will face disciplinary action from the State Bar on ethics charges. He could also face a lawsuit from the three accused players.
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