The taxpayer, a chef with a high school diploma, failed to include in his return the T4 slip from one of his four employment sources. Hogan J. found that the taxpayer had a due diligence defence, given his inexperience in the workplace, and given that H&R Block, who he hired to assist in his return, had not advised him to seek the missing T4 slip.
Hogan J. reviewed several s. 163(1) due diligence cases and noted (at para. 9) that the key distinguishing factor is the taxpayer's familiarity with the tax system; the less the taxpayer's experience, and the more complex the income scenario, the stronger the defence.