Punishment, for all involved?

As the verdicts are passed and punishment is doled out to those involved in the animal abuse in Vermont last year, I really only have one question to ask. Where is the penalty for the "undercover" investigator who did nothing to prevent the abuse? How is it that being accessory to the crime and doing nothing to prevent it doesn't make you additionally guilty of the crime? How is it that we can't track down and punish those who claim to defend the animal but when in time of trial, fail to defend it from the abuse they claim to detest?