“Of course all estimates are unsatisfactory; of course they will always be open to challenge in points of detail; and of course they may well be under-estimates rather than over-estimates as well. But what the Crown has to do in such a situation is, on the known facts, to make reasonable inferences. When, in paragraph 7(b) of the case stated, the Commissioners state that (with certain exceptions) the inspector's figures were 'fair' that is, in my judgment, precisely and exactly what they ought to be, fair. The fact that the onus is on the taxpayer to displace the assessment is not intended to give the Crown carte blanche to make wild or extravagant claims. Where an inference of whatever nature falls to be made, one invariably speaks of a 'fair' inference. Where, as is the case in this matter, figures have to be inferred, what has to be made is a 'fair' inference as to what such figures may have been. The figures themselves must be fair.” 7. Section 50(6) TMA provides that if, on an appeal, it appears to the Tribunal that an appellant is overcharged by an assessment the assessment shall be reduced accordingly but “ otherwise the assessment … shall stand good .” 8. In the decision of the Court of Appeal in T Haythornwaite & Sons v Kelly (HM Inspector of Taxes) (1927) 11 TC 657 Lord Hanworth MR, referring to a previous incarnation of this enactment, said, at 667: “Now it is to be remembered that under the law as it stands the duty of the Commissioners [and from1 April 2009 the Tribunal] who hear the appeal is this: Parties are entitled to produce any lawful evidence, and if on appeal it appears to a majority of the Commissioners by examination of the Appellant on oath or affirmation, or by other lawful evidence, that the Appellant is over-charged by any assessment, the Commissioners shall abate or reduce the assessment accordingly; but otherwise every assessment or surcharge shall stand good. Hence it is quite plain that the Commissioners are to hold the assessment as standing goods unless the subject – the Appellant – establishes before the Commissioners, by evidence satisfactory to them, that the assessment ought to be reduced or set aside.” 9. Similarly in Moschi v Kelly (HM Inspector of Taxes) (1952) 33 TC 442 in which the Court of Appeal upheld the decision of the General Commissioners that the unexplained source of a taxpayer’s wealth was business profits which he had not declared Somervell LJ said: “… of course, the onus was on the taxpayer to satisfy the Commissioners that the assessments were excessive.” … “It seems to me, looking at the matter broadly, as it was before the Commissioners, they were fully entitles to say that the taxpayer had not discharged the onus which lay upon him of establishing his contention that his money came from assets brought in from 1933.”