Error of law is not abuse of power:
Abuse of power by subordinate Tribunal:
What is abuse of power? Inability to apply law properly? Exercise of power in excess of what was intended? Exercise of power for a collateral purpose? These question however have to wait till decided in appropriate case. Presently the view of Lord Griffiths is that mere error of law is not abuse of power. In his own words:
The common law has ever since the decision in Philips v.Bury (1694) Holt K.B. 715 recognised that the visitor acting as a judge has exclusive jurisdiction and that his decision is final in all matters within his jurisdiction. The common law courts have through three centuries consistently resisted all attempts to appeal decisions of the visitor. The courts have however been prepared to confine the visitor to his proper role as a judge of the internal affairs of the foundation by the use of the writs of prohibition and mandamus. When I said in Thomas v. University of Bradford  A.C. 795:
“I have myself no doubt in the light of the modern development of administrative law, the High Court would have power, upon an application for judicial review, to quash a decision of the visitor which amounted to an abuse of his powers”I used the words “an abuse of his powers” advisedly. I do not regard a judge who makes what an Appellate Court later regards as a mistake of law as abusing his powers. In such a case the judge is not abusing his powers; he is exercising them to the best of his ability albeit some other court thinks he was mistaken. I used the phrase “abuse of his powers” to connote some form of misbehaviour that was wholly incompatible with the judicial role that the judge was expected to perform. I did not intend it to include a mere error of law.