"Looking at the matter first without reference to the authorities, I should have thought that the meaning of the expression concerned, in the context in which it is used, was fairly clear. The performance of an act, in this case the presentation of a complaint, is not reasonably practicable if there is some impediment which reasonably prevents, or interferes with, or inhibits, such performance. The impediment may be physical, for instance the illness of the complainant or a postal strike; or the impediment may be mental, namely, the state of mind of the complainant in the form of ignorance of, or mistaken belief with regard to, essential matters. Such states of mind can, however, only regarded as impediments making it not reasonably practicable to present a complaint within the period of three months, if the ignorance on the one hand, or the mistaken belief on the other, is itself reasonable. Either state of mind will, further, not be reasonable if it arises from the fault of the complainant in not making such inquiries as he should reasonably in all the circumstances have made, or from the fault of his solicitors or other professional advisers in not giving him such information as they should reasonably in all the circumstances have given him. With regard to ignorance operating as a similar impediment, I should have thought that, if in any particular case an employee was reasonably ignorant or either (a) his right to make a complaint of unfair dismissal at all, or (b) how to make it, or (c) that it was necessary for him to make it within a period of three months from the date of dismissal, an industrial tribunal could and should be satisfied that it was not reasonably practicable for his complaint to be presented within the period concerned. For this purpose I do not see any difference, provided always that the ignorance in each case is reasonable, between ignorance of (a) the existence of the right, or (b) the proper way to exercise it, or (c) the proper time within which to exercise it."
"Once a man knows of his right it is more difficult to say that it was not practicable to give notice within a reasonable time. If he reasonably does not discover his right until a short time before the last days of the three months have elapsed, then obviously it would probably not be reasonably practicable to give notice in time. This case has been concerned, however, because of the intervention of the Citizens Advice Bureau. What is the position if, knowing of your right, you ask another to take the necessary action? In my opinion, you cannot then be in a better position than if you had retained the power to act yourself. If you have retained a skilled adviser and he does not take steps in time, you cannot hide behind his failure. There may be circumstances, of course, were there are special reasons why his failure can be explained as being reasonable. Like my Lord I am, however, doubtful whether this situation depends on the skill of the adviser. The defence of not being reasonably practicable might fail, whether or not the adviser was skilled, if in fact he was properly acting."