The issue before the court was whether the taxpayers were entitled to a deduction for interest. A lot of matters were argued before the case reached the High Court but before the Full Court the Commissioner's contention was that the interest deduction should apportioned and disallowed under s 51(1) to the extent that it exceeded the partnership income.
Their Honours indicated that if a taxpayer's costs in deriving income were less than the actual income, the deductions would be allowable. However, if the costs exceed the income derived, the taxpayer's purpose for making the expenditure may be relevant in characterizing and apportioning the expenditure for the purpose of the general deduction provision. This may include the taxpayer's purpose for incurring the expenditure. Manson CJ, Brennan, Deane, Dawson, Toohey, Gaudron and McHugh JJ said (at ATR 622-3): "...The position may, however, well be different in the case where no relevant assessable income can be identified or where the relevant assessable income is less than the amount of the outgoing...the disproportion between outgoing and income, the whole outgoing is properly to be characterized as genuinely and not colourably incurred in gaining or producing assessable income, the