"We're considering any potential witness," Donald Bayne said after the long-running Duffy saga-turned-criminal-proceeding had its first day in front of a judge.
"At this point, it's too early to rule anything out. But please understand, this isn't being run as a personal or political vendetta."
In July, the RCMP charged the former Conservative senator with 31 counts related to his Senate expense claims. The charges include fraud, breach of trust and bribery.
Bayne said he hopes to skip a preliminary hearing and set a trial date at another court hearing next week. He and Crown attorney Jason Newbauer will talk this week about how soon the former TV broadcaster's trial can begin.
"This will be his first opportunity for a complete airing of all the evidence before an impartial tribunal and his opportunity to clear his name, to show that he's guilty of no wrongdoing," Bayne said.
The one big question on everyone's mind is how much the prime minister knew about the secret $90,000 payment made by his former chief of staff Nigel Wright to cover Duffy's contested Senate expenses.
The prime minister has said on many occasions he knew nothing about the plan to pay Duffy's costs.
The case won't turn into a political sideshow, Bayne insisted.
"This isn't a political case. This is a criminal case. It's going to be conducted professionally," he said.
"The very strong judiciary in the Ontario Court of Justice will not allow this case to be turned into a political circus and we certainly don't intend to conduct the matter that way."
That said, Bayne acknowledged Duffy's case "absolutely" could go to trial before the next federal election, set for Oct. 19, 2015. The trial itself could last between six and eight weeks, he said.
The senator's poor health should be taken into account when setting a trial date, Bayne added.
"You know he's had two open-heart surgeries," he said. "So part of our concern ... is his physical and emotional and mental health."
During question period Tuesday, the New Democrats jumped on the prospect of Harper on the witness stand.
"Will the prime minister attempt to hide behind parliamentary privilege to avoid testifying?" NDP Leader Tom Mulcair asked Harper.
"Obviously if you read the investigator's report, there's absolutely no reason to suggest I would do that," replied the prime minister.
"But ... I guess what I would say to the leader of the NDP, if anyone were to ask me about the misuse and inappropriate use of public funds, I would certainly suggest him as an expert witness."
That was a reference to the controversy swirling around New Democrat MPs who were ordered to reimburse taxpayers for salaries paid to aides who worked in satellite party offices.
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