New Democrat defence critic Jack Harris is questioning Lawson, Baird and Nicholson on the scope of the mission and whether Canadian soldiers are involved in ground combat.
Defence officials recently revealed that special forces operators who had been described as working in an "advise and assist" role have actually exchanged fire with Islamic State in Iraq and Syria (ISIS) forces three times.
On Thursday, New Democrat defence critic Jack Harris lodged a formal complaint against Prime Minister Stephen Harper for providing "misleading information" to the House of Commons on the scope of Canada's military efforts in Iraq.
The House of Commons voted in support of a six-month air bombing mission last October (the government doesn't need parliamentary approval to deploy the military).
The government committed 600 troops, one CC-150 Polaris air-to-air refuelling aircraft, two CP-140 Aurora surveillance aircraft, and the necessary air crews and support personnel. Canada also sent six CF-18 fighter jets and one dedicated airlift plane to enhance the refuelling, air surveillance and transportation capacity of coalition members.
Those are in addition to a commitment of up to 69 special forces troops who work on the ground with Iraqi forces.