"My lawyer would like to chat with you on the phone about the event," Duffy wrote in an October 2014 email that was entered into evidence at his trial on Friday.
The email said Duffy flew out for the Saanich Fair, a big local event in Lunn's riding, only to have his appearance dropped at the "last minute."
That happened, Duffy suggests, because organizers procured a different attraction: a version of the torch used at the 2010 Vancouver Olympics.
"My memory is you and your team decided that since you had the Olympic torch, my presence wasn't needed," Duffy wrote. "It was a last-minute call, but that's the way it is in politics."
Lunn, who lost his B.C. seat in 2011 to Green party Leader Elizabeth May, testified Friday he did not respond to Duffy's email.
"I didn't respond to anybody at all about any of this," Lunn said. "Obviously, it was in the news and I had no interest in being part of any of this. The RCMP, obviously, when they asked me, I co-operated and answered anything that I knew."
Lunn said there was a casual arrangement for Duffy to be at the Saanich Fair, but he testified Duffy did not attend the event and he was not dropped because of the torch.
"That might be Mr. Duffy's recollection," Lunn told the court. "The reality was this was a very casual arrangement, very casual discussion that happened about the possibility of him coming to the fair.
"It just never got solidified or firmed up."
And Lunn had a different explanation for why the appearance was cancelled: the local Conservative association didn't want to foot the senator's bills, he said.
Lunn said there was a request to pay some expenses, but the association rejected it and that's why the senator did not come.
The Crown argues Duffy improperly charged taxpayers to travel to Vancouver so he could attend a family event.
Duffy has pleaded not guilty to 31 charges of fraud, breach of trust and bribery in connection with his housing and travel expenses — part of a spending controversy that spawned the exhaustive forensic audit currently roiling the upper chamber.
Auditor general Michael Ferguson has delivered his report to the Senate and it is to be publicly released Tuesday.
The files of nine senators — two sitting, seven retired — are flagged for referral to the RCMP and expenses of 21 others are being questioned.
Earlier Friday, Duffy's lawyer Donald Bayne said it's too early to tell if the auditor's report would echo in the trial.
But he said it's not fair that the latest accused senators will be able to seek arbitration of their questioned expenses under a new procedure that wasn't available when Duffy was tripped up.
"It's self-evident," he said outside the court.
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