prove, or require the commissioner to prove, in justification of the assessment, that the non-disclosure which the particulars of the assessment assume, in fact, took place. In my view S. 170 (1) should be understood as precluding a taxpayer in proceedings other than an appeal (or a reference) under the Act from challenging an assessment on any ground. This means, of course, that where a taxpayer objects to an amended assessment on the ground that there was no failure to make a full and true disclosure, he alleges, in the words of S. 177 (1), that the assessment, both in amount and the specified particulars, is not correct.
In passing, the observation may be repeated that an inquiry as to the correctness of the amount or the particulars of an amended assessment under S. 170 (2) will in many, though not all, cases raise the same, or substantially the same, question as an inquiry whether the taxpayer has made a full and true disclosure. This circumstance supports the view which I have already expressed concerning the content of the first limb of S. 177 (1) for it would be curious if, upon an appeal under the Act, the former inquiry should be open and the latter precluded against the appellant.
The observations which have already been made are not without importance upon a consideration of S. 190 (b) which provides that upon an appeal the burden of proving that the assessment is excessive shall lie upon the taxpayer. The form of words chosen, and particularly the word " excessive", presents some difficulty. For the appellant it is said that to show that the assessment is not, in the circumstances, authorised at all is not to show that it is " excessive". That expression, it is said, is limited to questions relating to the quantum of the assessment and does not extend further. But again it may be said that in many cases where amended assessments have been made under S. 170 (2) the questions will frequently be the same. But whether or not this is SO the word " excessive" is capable of a much wider meaning than that ascribed to it by the appellant's argument and there is no reason for thinking that an assessment, made in purported but not justifiable exercise of a statutory power, may not properly be described as excessive; it purports to impose a specified liability and, upon appeal, the claim of the appellant is that he is not liable to pay any part of it. Whether the particular ground upon which he seeks to escape or reduce the liability merely touches the accuracy of the assessment or assails its validity as an assessment, he is, in the words of S. 185, "dissatisfied with the assessment because it purports to impose upon him a liability in excess of that to which he may lawfully be subjected and I can see no reason why, in either case, his complaint