2nd of all, I will state Turkish practice, which was shaped on European (Swiss and German in this case) law. keeping those in mind:
In a commercial relation/contract, there are certain obligations, where illegal activity of one party becomes a joint responsibility of other, like obligations toward employees and most importantly consumers' rights issues. So the stronger partners in a contract (ICAAN for example) usually put in protective measures against illegal (or just shady) activities of the other party to the contract. This usually in the form of (you must report your activities related to such legal obligations/regulations. Failing to do so, or upon discovery of any misconduct related to such regulations, we can and will reflect possible penalties and liabilities to your account and we will have right to immediate optional termination)... (My translation might be sucking a little)
If such a clause exist in a contract, you can claim in the court that you acted to the best of your ability to prevent any such misconduct by other party, even if you had not acted upon these conditions (if you can prove you were unaware of such misconduct...).