OTTAWA -- The government's plans to close what it calls "unfair" tax loopholes dominated question period on MPs' first day back in the House of Commons.

The Conservatives came at Prime Minister Justin Trudeau and Finance Minister Bill Morneau from a number of different angles on how they say the proposed changes will hurt middle class Canadians and small business owners.

Conservative Leader Andrew Scheer started things off saying he spent his summer talking to business owners who reject that the Liberal government thinks of them as tax cheats.

"We’ve already established that this isn't fair, and we know that it’s not compassionate, so why is the prime minister doing this? Because he’s drowning in debt and a drowning man will reach out and grab on to anything, and not care who he drags down with him," said Scheer.

Trudeau shot back, saying the Conservatives were defending "wealthy doctors."

"The member opposite and indeed the entire opposition has been going around the country telling every doctor they meet that they stand with them, that they will defend their rights to lower taxes than the nurses that work alongside those doctors. We don’t think that’s fair," said Trudeau.

Reviews have been mixed amongst doctors' reaction to the changes. The Canadian Medical Association has come out strongly against the government’s proposal, while a collection of more than 300 doctors from across the country have issued an open letter to Morneau, asking him to follow through on the changes, saying the existing tax benefits "are advantageous mostly to certain incorporated doctors with specific family structures."

From how the tax changes could impact fishermen, young female entrepreneurs and pizza shop owners, Conservative MPs took every question slot they had to take the government to task.

"Will the minister of finance come down to earth with the rest of us mortals and actually listen to what’s going on?" said Conservative deputy leader Lisa Raitt.

But, the Liberals didn't bite. Time after time the government continued to defend its position.

"By following through on our promise to deal with the tax system that was creating advantages for the richest among us, we know we’re going to make a positive impact in our economy. We are listening," said Morneau.

The Liberal government’s three-pronged plan was unveiled in Ottawa in July, and includes limiting a corporation's ability to convert income into capital gains and dividends, halting business owners from lowering their tax rate by sprinkling money to family members regardless of their involvement in the business through dividends or by paying them salaries, and restricting the ability for private corporations to recover taxes through passive investments.

The government says the biggest impact will be felt by those business owners who are making $150,000 a year or more, or those who have money to tuck away after contributing the annual maximum to RRSPs and TFSAs.

The federal government is now in a 75-day consultation window and will be soliciting feedback from people on its proposal until Oct. 2. Once the consultations are over, the government is expected to table legislation to implement their plan.

The New Democrats didn't ask about the tax changes, taking their question period slots to question the government to raise other issues, including nuclear disarmament; NAFTA renegotiations; and pensions.