As the federal ethics commissioner readies for a third look at Stephen Harper's former right-hand man, Mary Dawson is reminding Canadians her office can only look so far.

The commissioner is examining whether Harper's chief of staff Nigel Wright violated the Conflict of Interest Act when he gave Senator Mike Duffy more than $90,000 to repay his housing expenses.

Wright has since quit his job and Duffy has left the Conservative caucus over the issue.

Their dual resignations and Dawson's investigation have been repeatedly cited as steps the government has taken to deal with an issue presenting the Tories its most serious challenge since winning a majority in 2011.

In an interview with The Canadian Press on Friday, Dawson couldn't talk specifically about her probe into the matter as investigations are confidential.

But she stressed that in all cases, her office must examine whether someone broke specific conflict-of-interest rules, not just that their behaviour or judgement was questionable.

"We do have to find ourselves within the four corners of the Act and the code because it's not fair to the person being complained against just to not be aware what they were accused of," Dawson said Friday.

"Reputations are important so we take a fair bit of care to make sure we are not falsely concluding anything."

Her office is charged with upholding the Conflict of Interest Act, which governs the actions of some 3,000 public office holders, and the conflict of interest code, which specifically relates to MPs.

Ethics issues involving the Senate are left to the ethics officer there, so whether Duffy himself violated any rules will be decided by that body.

Her office also can't police the entire sphere of ethical behaviour, Dawson said.

An example is the 2009 investigation of the large novelty cheques the federal government was using to hand out grant money.

They were branded with the Conservative party logo — an activity many felt was a clear breach of ethics.

Except there's nothing in either the Conflict of Interest Act or code that made those cheques a problem, and Dawson concluded as much in her final report.

"Political activities are not particularly covered by either the act or the code," she said in the interview.

"It's important that people realize that maybe there is a lack there. Maybe it's not necessarily for this office to be looking after, but there should be some rules governing political behaviour."

3rd look at Wright

Wright is no stranger to Dawson.

Her office was involved in setting guidelines for his work as chief of staff to the prime minister after he left the private equity firm Onex Corp. (TSX:OCX) to work for Stephen Harper.

She also later investigated but cleared him of allegations he'd used his influential position to further private interests of friends at Barrick Gold Corp (TSX:ABX).

The current investigation into his relationship with Duffy has no apparent connection to Wright's corporate life.

The $90,000 payment has been characterized by the Prime Minister's Office as a gift to Duffy with zero expectation of repayment.

The PMO has also insisted there's no documentation suggesting otherwise.

The Opposition has suggested there is and has demanded the government turn it over.

If there is a paper trail, Dawson's office will turn it up — eventually.

Getting documents out of the House of Commons or cabinet in a timely fashion has proven a challenge for her in the past, though she said she's never seen a request for documentation completely denied.

"I can only do what I can find, but I have certainly got the power to compel, if necessary, documents, production of documents and witnesses and the person that's alleged to have contravened the act," she said.

"Generally, in fact almost every time, we have no resistance at all."

Dawson said her office moves as fast as it can to investigate but they are at the mercy of those involved.

Lawyers, resource constraints, even people going away on summer vacation can slow down the process, she said.

RCMP involvement can further complicate things as the Act allows criminal investigations to take precedence.

Her office was investigating activities related to another former adviser to the prime minister — Bruce Carson — but was forced to suspend that investigation once the RCMP began their own.

The RCMP is examining the issue of Senate expenses.

Dawson's office can fine people if they've missed deadlines they're given to produce information, but not if they're found in contravention of the Act.

She says fines are not that important.

"I think these people who are in public life really care about their reputations, that is their most valuable asset," she said.

"And if they've contravened an ethics rule, it's not a nice thing for them and if it's all over the newspaper or all over a report that's not nice either and I think that's pretty significant dissuading force."

The observation sections of her reports can also be a way to note behaviour she feels is unethical when it's not a clear-cut violation of the Act or code, she said.

"I think when we issue any report it's a fulsome report," she said. "We try to get to the bottom of the whole situation."

But advocacy group Democracy Watch disagrees.

They've repeatedly chastised Dawson's office for appearing to look the other way on what they see as major ethical violations, while at the same time criticizing existing laws as being ineffective.

"The Conservatives caused the Senate scandal, but they and the Liberals, NDP and Bloc Quebecois are all to blame for the weak, biased or ineffective lapdogs who are investigating the scandal," said Tyler Sommers, co-ordinator of Democracy Watch, in a statement earlier this week.

"Because they all failed during recent minority governments to choose strong watchdogs, and to pass measures to close loopholes and strengthen enforcement powers and requirements."

Both Democracy Watch and Dawson's office have called for changes to the Act, which came into force in 2007.

A House of Commons committee launched a mandatory five-year review of the act last winter, but has yet to issue a final report.