Carol Skelton, Porter's replacement at the helm of the Security Intelligence Review Committee, said board members were cautioned both in writing and in person about the do's and don'ts for political activities.
That was on top of guidelines from the Privy Council Office advising committee members against making political donations.
"Yes, there was a letter that went out from the ethics commissioner," Skelton told The Canadian Press.
"It just said: 'Don't give donations.'"
Porter, who is currently the subject of fraud allegations swirling around a $1.3-billion Montreal mega-hospital development, seemed to ignore that advice during his tenure on the committee, donating $2,200 to the federal Conservative party, public records show.
Porter also donated to the Conservatives prior to his appointment, which is allowed under the guidelines.
Porter resigned from the committee in November 2011 after revelations surfaced about his past business dealings. The Canadian government is trying to extradite him from the Bahamas, where he runs a medical clinic.
Porter, a medical doctor who has been self-diagnosed with cancer, has yet to return a message left with a receptionist at his clinic in the Bahamas.
Prime Minister Stephen Harper appointed Skelton to SIRC in June 2010. She recalled a meeting with PCO officials after her appointment, at which she was again cautioned against making donations.
"I can remember going to PCO and going through it all," Skelton said. "They talked a lot about different things. No, they made us aware (of the guidelines for donations)."
Skelton was already a member of the Privy Council from her days as a cabinet minister at the time of her SIRC appointment, and said she was already familiar with the rules. She has since left SIRC.
"You have to look at your own ethics and everything, and decide what's right and wrong, and what's right and wrong in your lifestyle," she said.
"I think the prime minister expects all of us to do that when we accept the position."
SIRC executive director Michael Doucet has said PCO briefs all new appointees on, among other things, the rules that apply to them when it comes to political activities.
The Office of the Conflict of Interest and Ethics Commissioner says it does not advise SIRC members against making political donations.
Instead, PCO's Accountable Government guide sets out rules for political activities. The ethics commissioner may have referred SIRC members to that guide, a spokeswoman for her office said.
"Our office has continued to advise public office holders to refer to that document, noting that it is administered by PCO," Margot Booth said in an email.
"It still contains guidelines regarding political activities, including political contributions, but we do not administer it nor do we advise as to its contents."
The guide advises public-office holders not to participate in a political activity that might "cast doubt on the integrity or impartiality of the office." Political donations are listed as one such activity.
PCO, meanwhile, refused to say Tuesday if Porter's donations while at SIRC will be investigated.
"Mr. Porter is no longer a public office holder. We do not comment to make on the cases of individuals," spokesman Raymond Rivet said in an email.
On Tuesday, the Liberals and New Democrats grilled the Conservatives in the House of Commons over Porter's donations. Tory MP Pierre Poilievre dodged the donation question, instead saying none of the fraud allegations against Porter have anything to do with his former role at SIRC.
Porter is among the five people named in arrest warrants issued by Quebec's anti-corruption squad in the McGill hospital case. Also named are former SNC Lavalin senior executives Pierre Duhaime and Riadh Ben Aissa, Yanai Elbaz and Jeremy Morris, the administrator of a Bahamas-based investment company.
The warrants say the men are wanted on numerous charges — including fraud, breach of trust and document forgery. They say Porter and Elbaz are suspected of having accepted bribes from some of the others.
In addition to being head of SIRC, Porter was also the director general of the McGill University Hospital Centre when the alleged fraud occurred.