Too big of a rush to blow up Tank?

So now it turns out that Tank Johnson, defensive lineman for the Chicago Bears, frequently in trouble with the law and the league in the past year or two, did NOT have an alcohol level over the legal limit, when he was pulled over recently for drunk driving. He's not being charged. But, shortly after the incident, the Bears released him. Unfair? Maybe. But then, why is a guy in his situation drinking anything and driving? There are more societal moral issues being played out in the sports world than we think...