A rule of law is a principle, a legal term, that has been adopted by the legislator, whether that be internationally or nationally. We can say that a rule of law communicates a sense of order and submission to known laws. Furthermore, we can also say that a rule of law communicates the governing leaders' sense of responsability before the legal authorities, those being the court system.
Once a principle becomes a rule of law, a court is expected to render its judgment by interpreting the exact text that identifies the rule of law. Consequently, the court is forbidden to interpret the text identifying the rule of law accordingly to a common meaning or to take personal considerations in interpreting the text.
Genocide is an international rule of law originally defined in the UN General Assembly Resolution 260 A III of December 9, 1948 and, subsequently, transferred into the Rome Statute of 1998. Genocide is an international crime that must see the perpetrators of the crime of Genocide brought to justice.
Rome Statute 1998 defines the rule of law of the crime of Genocide as follows:
Article 6
Genocide
For the purpose of this Statute, "Genocide" means any of the following acts committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such:
(a) Killing members of the group;
(b) Causing serious bodily or mental harm to members of the group;
(c) Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;
(d) Imposing measures intended to prevent births within the group;
(e) Forcibly transferring children of the group to another group.
The full text of the UN General Assembly resolution 260/1948 can be found here
