Related Rule
Luxembourg
Practice Relating to Rule 151. Individual Responsibility
Luxembourg’s Law on the Repression of War Crimes (1947) provides for the prosecution and sentencing of non-nationals of Luxembourg who have committed war crimes, “if such infringements have been committed at the occasion or under the pretext of war and if they are not justified by the laws and customs of war”. 
Luxembourg, Law on the Repression of War Crimes, 1947, Article 1.
The Law also provides for the prosecution, as co-authors or accomplices, of persons who, “without being superiors in rank of the principal authors, have aided those crimes or offences”. 
Luxembourg, Law on the Repression of War Crimes, 1947, Article 3.
Luxembourg’s Law on the Punishment of Grave Breaches (1985) provides for the punishment of perpetrators of grave breaches of the 1949 Geneva Conventions as well as of persons who build, hold or transport instruments or other devices in the knowledge that they are intended to be used in the commission of a grave breach. 
Luxembourg, Law on the Punishment of Grave Breaches, 1985, Articles 1–3.
It also provides for the punishment of persons who, “without being superiors in rank of the principal authors, have aided those crimes or offences”. 
Luxembourg, Law on the Punishment of Grave Breaches, 1985, Article 5.
Luxembourg’s Law on the Punishment of Grave Breaches (1985) states that a civil action against the perpetrator of offences provided for in this law can only be undertaken before a civil court. However, it provides for the possibility for the (criminal) court to order the restitution of seized objects and exhibits to the entitled person if they are not to be confiscated. 
Luxembourg, Law on the Punishment of Grave Breaches, 1985, Article 14.