"In my speech in the Bedfordshire case[1995] 2 AC 633 , 740-741 with which the other members of the House agreed, I pointed out that unless it was possible to give a certain answer to the question whether the plaintiff's claim would succeed, the case was inappropriate for striking out. I further said that in an area of the law which was uncertain and developing (such as the circumstances in which a person can be held liable in negligence for the exercise of a statutory duty or power) it is not normally appropriate to strike out. In my judgment it is of great importance that such development should be on the basis of actual facts found at trial not on hypothetical facts assumed (possibly wrongly) to be true for the purpose of the strike out."