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Richmond Centre-Marpole MP Chak Au.DARRYL DYCK/The Canadian Press

Two government ethics experts say federal rules need to change to prevent members of Parliament from holding more than one public office at a time, after Chak Au continued to serve as a municipal councillor in Richmond, B.C., when he was elected a Conservative MP.

Mr. Au has served as a city councillor since 2011, and was first elected federally in April.

Following that election, Mr. Au said he had planned to wait until at least January to resign in order to help the city avoid the cost of a by-election, according to Richmond News. It then reported last month that he had since decided to stay on until the fall municipal elections.

However, after an inquiry from The Globe and Mail, a spokesperson for Conservative Leader Pierre Poilievre’s office, Katy Merrifield, said Mr. Au does plan to resign and is waiting for confirmation that no by-election will be required.

She said in a statement that a by-election would cost taxpayers more than $1-million. “MP Au will be resigning his municipal seat once he receives this confirmation from Richmond City Council,” she said.

Kenny Chiu, Mr. Au’s chief of staff and the president of his local electoral district association, said the MP was committed to the hours involved in performing both roles.

Mr. Chiu confirmed that Mr. Au has donated his net municipal salary to charity.

“He’s extremely, understandably busy, to the point that we are very concerned of his health,” Mr. Chiu said. “I’ve been a member of Parliament myself and I would not be able to handle that kind of a schedule and demand, but I’m not Chak Au.”

Dalhousie University professor Lori Turnbull said that although it is common for someone to hold an elected office and then run for another, nobody would expect a candidate to hold both positions afterward.

“The understanding is being an MP is a full-time job,” Prof. Turnbull said. Holding two “would suggest that you’re not fully devoted to your role as an MP.”

“It’s not in the public’s interest for somebody to be using at least one of their elected roles as a side hustle,” she said.

York University associate professor Ian Stedman said he would want new rules to be explicit that it is not permissible for a person to hold two elected positions that could potentially come into conflict.

The Conflict of Interest and Ethics Commissioner’s Office said in an e-mailed statement that there is nothing in the code that prohibits this.

The Conflict of Interest Code for MPs “does ​not prohibit Members who are not ministers or parliamentary secretaries from engaging in outside activities as long as they are able to fulfill their obligations under it,” said director of communications Melanie Rushworth.

MPs must disclose any outside sources of income to the Commissioner’s office, but Mr. Au’s conflict details have not yet been added to the office’s public registry.

“The initial compliance process has not yet been completed with MP Au,” she said.

Guy Giorno, a former chief of staff to prime minister Stephen Harper who is now the practice leader in political law at Fasken Martineau DuMoulin LLP and advises clients on government accountability and ethics, says that many provinces do have rules against MPs serving on municipal councils.

For example, Alberta and Ontario have such restrictions, but British Columbia does not.

Mr. Giorno added that under Parliament’s conflict-of-interest code, Mr. Au’s second job would create a “private interest” that could bar him from voting or debating on matters that affect Richmond.

Prof. Stedman noted that conflicts could be difficult to avoid, as Canadians are increasingly looking to have the federal government involved in municipal issues, such as housing.

Mr. Au’s two roles had also raised concerns among fellow Richmond city councillors, though outgoing mayor Malcolm Brodie was supportive of Mr. Au staying on.

“He’s effectively fulfilling his civic role slightly differently than before he got elected,” Mr. Brodie said. “I think it’s a reasonably unique situation, I don’t expect to see it again in the future, but I take it for what it is.”

Councillor Alexa Loo said it made sense for Mr. Au to keep the council role until January, because it prevented the cost of a by-election. “Now it’s time to pick a lane and do that job wholeheartedly,” she said.

Councillor Carol Day said there is a “laundry list” of reasons Mr. Au should not have both roles.

“Would you rather do one job well or two jobs poorly?” she said.