Law is of the state,by the state and for the state.
Every state is the conscience keeper ,protector of the people of that country.
State wisdom is law.
 Only the court of that state, once again that court is also only the wisdom of that state law, can authoritatively comment upon the administration of law,application of law.
  Law is the reflection,manifestation of state-supremacy,state wisdom
Every state is guided by its own personal or political perception.
Tax laws are no different.