OTTAWA – Prime Minister Justin Trudeau is defending Finance Minister Bill Morneau's use of an ethics loophole to maintain ownership of shares in his family’s business, saying he was acting on the advice of the ethics commissioner, who cleared it.

CTV News exclusively reported Tuesday that Morneau continues to own shares in his family’s business Morneau Shepell through a corporate structure that keeps him from having to divest or put his shares in a blind trust.

"He followed all of her advice," said Trudeau, speaking about the advice Conflict of Interest and Ethics Commissioner Mary Dawson gave Morneau when he was elected, that a blind trust for his shares was not required.

Dawson told CTV News Tuesday that she interprets the law as it stands to refer to directly held stocks, and not indirectly held stocks, as is the case with Morneau.

Securities filings accessed by CTV News show that he owned as many as two million shares in Morneau Shepell in 2011 -- today worth more than $40 million, through a numbered company he set up in Alberta.

Morneau personally holds a one third stake in the Calgary-based company, with the remaining two thirds owned by another numbered corporation in Ontario that Morneau solely owns.

"We expect that when she gives advice to do something or behave in a certain way, we follow that," Trudeau said in Question Period, where he fielded questions from both the Conservatives and New Democrats over Morneau’s shares and potential conflicts of interest.

Trudeau did not say, when asked, when he found out that Morneau’s assets were not in a blind trust, and chalked the opposition questioning up to personal attacks.

In Question Period, NDP MP ethics and deputy finance critic Nathan Cullen accused Trudeau of not taking responsibility, and throwing the ethics commissioner under the bus.

Morneau's continued ownership of shares in the firm creates numerous conflicts of interest, the opposition charges, saying he, through Morneau Shepell, stands to benefit from decisions he makes as the finance minister; including the potential conflict Morneau has as the minister who tabled legislation that would impact pension transfers, something that would fall under Morneau Shepell’s purview.

On Tuesday, Morneau wrote to Dawson asking for a meeting discuss whether further steps, like putting his assets in a blind trust, would be appropriate. Morneau was not in the House of Commons on Wednesday.

Opposition says Morneau's lost credibility

Earlier Wednesday, Conservative MPs said that Morneau has lost credibility as finance minister as a result of the controversy surrounding his personal finances.

"First of all he needs to come clean about what does he really have… and come clean with Canadians because he needs to restore the credibility and integrity of that office," Conservative MP Marilyn Gladu told reporters on her way in to Wednesday’s Conservative caucus meeting.

"He’s making decisions about pension plans and about things that benefit Morneau Shepell… it would be hard to imagine that he would not benefit from that money," said Gladu.

Conservative MP Tony Clement called it hypocritical for Morneau to use an ethics loophole, while going after business owners for using tax loopholes through the Liberal’s contentious tax reform that is receiving rolling tweaks this week.

"The stench of hypocrisy is quite strong on this and I think he’s lost all credibility, quite frankly," said Clement.

Ethics Commissioner noted loophole in 2013

Morneau has been able to maintain indirect ownership by using a loophole in the ethics law that Dawson says she flagged in 2013, when the Conservatives were in power.

Dawson first confirmed on CTV’s Power Play Tuesday that Morneau does not directly own the shares -- instead, he owns them indirectly through a holding company.

Generally, as the law operates now, if someone has stock, it’s a "controlled asset." Upon becoming a public office holder, the shareholder would be required to either divest or put them in a blind trust. However, shares that are held by a corporation are not considered to be directly held by the individual.

Dawson told CTV News that she interprets the law to refer to shares that are held directly, and not those held indirectly, as is the case with Morneau. This loophole is something she has previously advocated should be amended, to count shares that are directly and indirectly held.

When Morneau became finance minister, Dawson set up an ethics screen, where his chief of staff is responsible for making sure Morneau would not be involved in government business that could affect the company.

With files from CTV News’ Glen McGregor