Keith Beardsley, who served for five years as Harper's deputy chief of staff for issues management, warned the court proceedings could leave Harper and his staff scrambling to put out fires.
"Duffy, being the showman, he'll release whatever he can release when it's the most damaging and that's what the party, the prime minister, PMO has to be on guard for. And they just sit and wait for it to come and you have no control over those types of situations, you simply react," Beardsley told CBC News.
"So as we get closer, the longer this goes on and the closer it gets to the election date, the more damaging that type of information is."
Court proceedings begin Tuesday for Duffy, a day after MPs return to Parliament for the fall sitting, and it's possible things could be in full trial mode in 2015 — just in time for the pre-election season.
A source tells CBC News that Duffy's lawyer, Donald Bayne, is considering skipping the preliminary phase to move to trial quickly.
Duffy is facing 31 charges in connection with allegations of misspending of public money. The charges include fraud, breach of trust and bribery of a judicial officer. The RCMP laid the charges July 17, after a year-long investigation relating to Duffy's Senate living allowance, expense claims, awarding of consulting contracts and a $90,000 payment from the prime minister's former chief of staff, Nigel Wright.
It's expected that Tuesday's first court appearance by Bayne will set a date for a judicial pre-trial and determine the availability of a judge and courtroom. Bayne will also ask the Crown for full disclosure of all documents, discs and information he needs to defend Duffy.
The bigger decisions, like whether to wave a preliminary trial, are expected to come later.
Moving to trial
Lawrence Greenspon, a top criminal lawyer in Ottawa who is not working on Duffy's case, says if Duffy doesn't waive the preliminary hearing it will be difficult to see a trial start before 2016.
"If there's an interest in getting to trial as quickly as possible, waiving the preliminary would be a major step in that direction," Greenspon said.
Earlier this summer Duffy said he was "keen" to have his story heard as soon as possible.
"I would like to get this matter before the judge as soon as possible. Early 2015 is fine with me. I'd like to get it settled so Canadians will know the real story," Duffy told CBC News outside his home in Cavendish, P.E.I, in July.
Beardsley said accelerating the proceedings could maximize political damage for the Conservatives.
"This is the best way to get even is to have all this going on just as an election is ramping up. So from his side I would see it's in his best interest to do so," Beardsley said.
A trial could take months to complete because of the mountain of documents and emails that will be placed in evidence.
The emails expected to be submitted include exchanges between Duffy and Wright as well as ones between Duffy's original lawyer, Janice Payne, and members of the PMO regarding the $90,000 cheque.
At a news conference last October, Bayne insinuated he also has evidence showing Harper knew something about the $90,000 repayment.
"I do have information. I cannot and I'm not presently prepared to divulge it. It is, I think it is, all of this information you would find extremely germane …," Bayne told reporters.
Harper has always said that he didn't know about the payment until it was revealed in the media.
It's expected that Senate bureaucracy, members of the Senate's board of internal economy, Senate leadership, former and current officials in the Prime Minister's Office and likely Harper himself will be called to the stand to testify.
Harper's office has said it is difficult to imagine that he would have any relevant information to share in Duffy's trial.
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