Executive Summary: Key Legal and Evidentiary Issues

• Central issue concerned whether interest paid by Bank of Montreal (BMO) to U.S. tax authorities on overdue tax liabilities is deductible under section 9 of the Income Tax Act (Canada) and not precluded by subsection 18(1).

• BMO argued that interest on tax arrears should be treated analogously to interest on tax refunds, which is considered business income, and thus deductible.

• The Respondent maintained that such interest is not deductible as it is an expense incurred after the income-earning process, relying on the Roenisch principle and supporting case law.

• The court analyzed whether the interest was incurred for the purpose of earning income or was a consequence of having earned income.

• Statutory interpretation of sections 9, 18(1)(a), 18(1)(t), and related provisions was central to the decision.

• The court held that the interest is not deductible, and costs were awarded to the Respondent.

Background and facts

Bank of Montreal (BMO), a Canadian chartered bank, conducted business through a branch in the United States. For the 1997 to 2001 taxation years, BMO was subject to U.S. federal income tax on business profits attributable to its U.S. permanent establishment and was also subject to New York City municipal income tax for the period it had a branch there. BMO paid all outstanding balances it believed it owed based on its tax returns as filed by the return-filing deadline.

In 2004, the U.S. Internal Revenue Service (IRS) completed an audit of BMO’s U.S. branch operations for its 1997 to 2000 taxation years and assessed BMO for additional U.S. federal income tax and interest. BMO was also assessed for additional New York City municipal income tax and interest. In 2006, BMO was assessed for additional U.S. federal income tax and interest with respect to its U.S. branch operations for its 2001 taxation year.

The total amount of interest owed by BMO to the U.S. tax authorities was $8,975,467 (CAD) in connection with the audit completed in 2004 and $1,829,839 (CAD) in connection with the 2006 audit.

For Canadian tax purposes, BMO claimed the deduction of the interest paid to the foreign tax authorities in the calculation of its income for the 2004 and 2006 taxation years. The Minister of National Revenue disallowed these deductions pursuant to section 9 and paragraph 18(1)(a) of the Income Tax Act. BMO appealed to the most recent notices of reassessment dated October 31, 2019, for the 2004 taxation year, and March 6, 2023, for the 2006 taxation year.

Arguments of the parties

BMO argued that an analogy must be made between interest on tax arrears and interest on tax refunds, which supports the argument that the interest payment is an allowable expense under section 9 of the Act. BMO relied on Canada v. Irving Oil Ltd. and Munich Reinsurance Co. v. Canada, arguing that courts have recognized that interest on tax refunds constitutes income from a business for the purposes of the Act because it arises from a business decision on how much to pay in respect of a tax liability pending a final determination. BMO also argued that Parliament’s intent and other provisions, such as paragraph 18(1)(t) and sections 20(11), (12), (12.1), and 126(2), should be considered in interpreting paragraph 18(1)(a).

The Respondent argued that BMO misinterpreted the case law and that the decisions cited do not support the proposition that any decision to pay disputed taxes results in an income inclusion or deduction because any such decision is a business decision. The Respondent’s main argument was that interest expenses incurred after the income-earning process are not deductible pursuant to the Roenisch principle, and that to allow a deduction for the interest expense would result in an inaccurate picture of BMO’s income for the relevant taxation years. The Respondent also argued that the absence of any mention of interest on foreign income tax in paragraph 18(1)(t) should not be construed as an endorsement of its deduction under subsections 9(1) and 18(1).

Discussion of policy terms and statutory provisions

The dispute centered on the interpretation of section 9 (income computation), paragraph 18(1)(a) (general limitation on deductions), and paragraph 18(1)(t) (specific limitation on amounts paid under the Act) of the Income Tax Act. The court examined whether the interest on overdue foreign tax liabilities was an expense incurred for the purpose of earning income or merely a consequence of earning income. The court also considered whether specific provisions regarding foreign tax credits and deductions for foreign taxes could justify the deduction of interest in this context.

Court’s analysis and outcome

Justice MacPhee held that the interest paid by BMO to U.S. tax authorities was not deductible under section 9 and was precluded by subsection 18(1)(a) of the Act. The court found that the interest was not incurred to earn income but was a result of income already earned and taxed. The Roenisch principle, as reaffirmed in Potash Corporation of Saskatchewan Inc. v. K., was applied: an expense that would not have been incurred unless there was income is not an expense incurred to earn income. The court rejected BMO’s analogy to interest on tax refunds and its reliance on other statutory provisions, finding that the statutory scheme did not support the deductibility of the interest in question.

Final order and costs

The court answered the question put to the Court pursuant to section 58 of the Tax Court of Canada Rules (General Procedure) in the negative: the interest claimed by BMO is not deductible under section 9 of the Income Tax Act and is precluded from deduction by subsection 18(1). Costs were awarded to the Respondent for both stages of the application. The parties were given 30 days to reach an agreement on costs, failing which the Respondent would have a further 30 days to file written submissions on costs and the Appellant would have yet a further 30 days to file a written response. If no agreement or submissions were received within the time limits, one set of costs would be awarded to the Respondent as set out in the Tariff. No specific monetary award was granted to BMO; the Respondent (His Majesty the King) was the successful party and entitled to costs as determined by the court’s tariff or further submissions if necessary.