Legal validity has to be distinguished from other, more demanding, normative ideas, such as moral bindingness or legal optimality. That a law is valid when it is defined as valid by a rule of recognition which is accepted by officials. In addition to Hart's criteria, I believe that for a law to be valid the system of law of which it is a part must itself be valid. For a system of law to be valid, the rule of recognition must be accepted by not just the officials, but by the society generally, and the members of the society must have the ability to change the laws which will govern them.
Seven points that defends the legal validity of international law:
(1) Law is not always made by a definite political authority:
Municipal law, according to the modern conception of law, docs not mean the command of a determinate human superior. It must partake of other elements.
It is the result of the social needs of the community. It is derived from various sources like customs, religion, judicial precedents etc. Likewise, international law is the result of the specific needs of the stales and is derived from similar sources.
(2) Law is not obeyed for fear of punishment: The sanction behind ordinary law is not the coercive power of the state but it is public opinion instead. The same principle holds good in the case of international law.
(3) Regular international tribunals exist:
Just as we have courts for the interpretation of ordinary law, similarly international courts exist for the interpretation of international law like the International Court of Justice and the Permanent Arbitration court, etc.
Besides there are prize courts in every country to try prize cases according to international law
(4) International Law-a part of Municipal Law :
Civilized countries like the England and the U.S. A. have recognized international law as a part of the law of their land. Legislatures of these countries cannot . make law which is contrary to international law.
(5) International Law is developing into a concrete law:
It said that international law is not well defined. This is true as international law is not made by an elected legislature. But now every effort is being made to codify international law. For instance Paris conference, London conference, Brussels conference and Geneva convention were held to discuss the problems about the codification of international law.
After the first World War, League of Nations appointed codification commission and after the second world War U.N.O. established a commission for the same purpose. These conferences, conventions and commissions have made progress. They have succeeded in their efforts to codify many ripe topics of international law.
(6) International Law is being willingly adopted by the States:
International law is based on the consent of the states. It is more a matter of policy than a matter of law for them. But the means of transport and communication have already improved a lot.
They have reduced the wide world into a compact complex. Interdependence of states has increased and is ever increasing. They have to rely more and more on international law.
No assembly frames a constitution against the rules of international law. The same can be said about the heads of state. After the Second World War, Nuremberg Trials were held to try Nazi Prisoners of War.
The fact is that states, in breaking the law of nations, never deny its existence. But recognize its existence". International law is thus a law, and is not limited to canons of positive morality.
(7) No negation of sovereignty of the State:
Lastly, it is pointed out that the concept of absolute sovereignty is merely an abstraction, it may be true as a pure legal theory but it is held to be inconsistent with actual practice. Sovereignty of the state does not imply that the slates cannot mutually agree to follow certain rules of conduct for common interest and well-being. Without such rules there will be separate state spheres of intensive order.
No state is self-sufficient. Hence it cannot sustain an isolated existence. The concept of absolute sovereignty of the state is, therefore, held to be a fiction by many modem political philosophers. Laski aptly remarks that it will be of lasting benefit if the whole concept of sovereignty is expunged from political science.