Failure to act to prevent another from commiting a crime?

An interesting and 'dicey' question. Although the law, in some instances, may excuse someone who, without criminal intent or interest in the offense, who simply stands by mute, is not accountable for the crime. However - SOME jurisdictions DO criminalize the act by statute, by charging such persons for failing to notify the authorities of their knowledge of an impending criminal event. The theory, no doubt, being that ANY honest citizen would WANT to notify law enforcement of a potential criminal act about to be committed.