McIntosh v. The Queen, 2011 DTC 1116 [at at 625], 2011 TCC 147 -- summary under Subsection 169(1)

The taxpayer alleged that his employer had under-reported source deductions on his T4 slips. D'arcy J. found that the Tax Court of Canada lacked jurisdiction to hear the case. The Tax Court may only hear appeals from an assessment - matters pertaining to the "tax payable" in a taxation year. The taxpayer's appeal concerned tax collection - a matter of "tax owing" - and that is outside the Tax Court's authority.