After finding that a lump-sum payment to cover support-payment arrears could be considered as an amount payable on a periodic basis, even though it was less than the amount initially anticipated, the Directorate went on to note:
The Court of Appeal judge decided to credit the amount of $XXXXXXXXXX, which consisted of expenses incurred by Monsieur for the benefit of the child, against the balance of the arrears owed to Madame by Monsieur. From a legal point of view, that mechanism is known as "judicial set-off". It is a method of extinguishing a debt in the same way as payment. However, as stated in S. Fisher v. The Queen, 2000 DTC 3612, there is a significant difference between a payment and a set-off. Generally speaking, where there is set-off of a debt, the debt cannot be said to have been paid unless the parties agree between themselves that the set-off constitutes payment.
In the present situation, the two parties had not agreed between themselves that the set-off could be a method of payment of the obligation. Consequently, we are of the view that the amount of $XXXXXXXXXX cannot be considered a payment. Since Monsieur did not "pay" that amount, he will not be able to deduct it as support because of the wording of paragraph 60(b), which refers to amounts paid. The reasoning is the same for Madame. Since she did not receive that amount ... .