counsel or information, shall be liable for aiding and abetting. Furthermore, whoever, acting against a particular legal duty of preventing the prohibited act, facilitates its commission by another person through his omission, shall also be liable for aiding and abetting. Article 19. § 1. The court shall impose the penalty for instigating, and aiding and abetting within the limits of the sanction provided in law for perpetrating. § 2. In imposing the penalty for aiding and abetting, the court may apply extraordinary mitigation of punishment. Article 20. Each persons co-operating in the perpetration of a prohibited act shall be liable within the limits of his intent or a lack of it, irrespective of the liability of others co-operating in the perpetration. Article 21. § 1. Circumstances pertaining to an individual, excluding or mitigating, or aggravating his criminal liability shall be taken into account only with regard to the person they pertain to. § 2. If an individual circumstance regarding the perpetrator, even if it is conducive only to aggravation of penalty, constitutes a feature of a prohibited act, the person co-operating shall be held liable under criminal law, for this prohibited act, when he knew about this circumstance, even though it did not pertain to himself. § 3. With regard to a person co-operating to whom the circumstance referred to under § 2 does not apply, the court may apply extraordinary mitigation of punishment. Article 22. § 1. When the commission of an prohibited act was only attempted, the subject specified in Article 18 §§ 2 and 3 shall be liable as for an attempt. 7