An RCMP affidavit released last week suggests that Michael Runia was phoning at the behest of Conservative Senator Irving Gerstein as the Prime Minister's Office and party leadership scrambled to rein in a scandal over Duffy's spending.
Runia is the Ontario managing partner for Deloitte's audit section and the auditor of record for the Conservative Fund of Canada, the Conservative Party's fundraising arm.
Gerstein runs the Conservative Fund.
While the Senate's internal economy committee invited three Deloitte representatives to Thursday's meeting, Runia wasn't one of them.
Liberal Senator George Furey argued at the end of the meeting that the committee needs to hear from Runia, but outgoing committee chair Gerald Comeau overruled Furey's motion.
Comeau said it was up to the RCMP to investigate the call if they so chose.
"Consider this a challenge of your ruling, chair," Furey said.
Senators voted to sustain Comeau's ruling, meaning the committee won't call Runia to explain the call.
'I wanted that call ... to end'
Gary Timm, who was in charge of Duffy's audit, told senators on the committee that Runia phoned him once.
"He wanted to know if Senator Duffy were to repay, how much would that be. I told him I can't divulge or disclose any confidential information. He understood my reply and I directed him to public information," listing senator entitlements, Timm said.
"It was a short call and it ended there."
Asked whether Timm tried to find out why and on whose behalf Runia was calling, Timm said no.
"I wanted to keep everything confidential and I wanted that call, like I said, to end shortly... He called me about that one question," Timm said.
Despite Timm's response to Runia, a March 21, 2013, email from then-PMO staffer Patrick Rogers suggested he had information about Deloitte's not-yet-drafted report. The email was contained in the 80-page RCMP affidavit. None of the allegations in the affidavit have been tested in court.
Rogers said in an email that Deloitte wouldn't make a finding on Duffy's residency, something borne out in the final report.
"That paragraph was troubling for us too," said Alan Stewart, a partner at Deloitte Forensic.
Senators tried to drill down into who could have provided information to Conservative officials, with a dozen people working on the audits of Duffy, Patrick Brazeau, Pamela Wallin and Mac Harb.
Stewart said some team members worked on only small aspects of the Senate audits. The files were kept in a secure room with padlocked filing cabinets and two laptops with digital files cut off from the internet. None of the team members were allowed to bring mobile devices into the room, he said.
Still, seven people had access to the full report, Senator Elizabeth Marshall pointed out.
"Are you confident that the confidentiality of the report was maintained?" she said.
"Yes," Timm and Stewart replied.