Private citizens writing cheques to cover expenses for parliamentarians is a "very common practice" in the House of Commons, the former executive assistant to Mike Duffy testified today.

Diane Scharf was questioned for a second day about her testimony that Duffy arranged to have her reimbursed for paying the monthly fees of her Senate cellphone.

Court heard on Tuesday that Scharf received cheques through Gerald Donohue, an associate of Duffy, after the Senate administration said it would not cover the fees for her Senate phone. Scharf received four cheques from Donohue's family company for the fees.

Scharf, who has worked in a number of parliamentary offices, said this is business as usual.

"This is a very common practice at the House of Commons," Scharf told Crown prosecutor Jason Neubauer. "I'm quite accustomed to this. We had staff, people working in our office paid for by a businessman in Toronto. You have to be creative sometimes to get bills paid."

CBC News asked Conservative MP David Sweet, for whom Scharf worked in the past, for reaction to her testimony, and whether he had ever used an outside person to make payments to staff or heard of the practice as being a common one.

Sweet replied with this statement: "I'm not going to comment on the trial or anything said at the trial. I have the upmost respect for taxpayers and have never engaged in this practice."

Another MP, Health Minister Rona Ambrose, responded with the identical statement when asked the same questions.

A spokesperson for the House of Commons said MPs are given resources to carry out their parliamentary functions, and the Commons' conflict of interest code prohibits MPs from receiving any gifts or benefits that "might reasonably be seen to have been given to influence the member."

​Duffy has pleaded not guilty to 31 charges of fraud, breach of trust and bribery related to expenses he claimed as a senator and later repaid with money from the prime minister's then chief of staff Nigel Wright. The trial, which began April 7 in the Ontario court of justice in Ottawa, is in its 30th day.

'Back-door way of getting things done'

The court has heard that Donohue had been awarded a series of Senate research contracts with Duffy worth nearly $65,000.

The RCMP have said Donohue received the money for "little or no apparent work." Instead, the Crown alleges, that pool of money was used by Duffy, through Donohue, to pay for a series of expenses, some of which the Crown says would not have been covered by the Senate.

Duffy's defence lawyer Donald Bayne has argued that while it was "administratively irregular" to not have these expenses paid out through Senate finance, the action was not criminal.

Diane Scharf, a former executive assistant to Mike Duffy, continue her testimony Wednesday in an Ottawa courtroom at the trial of the suspended senator. (Greg Banning/Canadian Press)

Scharf worked for Duffy for six months in 2011 while his full-time executive assistant Melanie Mercer was on maternity leave.

In a previous interview with police investigating Duffy, court heard that Scharf said: "When I worked for members of Parliament and cabinet ministers, this was often the way invoices were taken care of and it's still done at the House of Commons."

"It's sort of a back-door way of getting things done," she told police.

Bayne suggested there was nothing wrong with this arrangement. Scharf, Bayne said, was being reimbursed for these fees through funds that had paid for Donohue's contract with Duffy.

"The funds that were used to pay the plan that enabled you to do the work you were hired to do, Senate work, those funds were office budget funds if they came out of that contract, right?"

"That's correct," Scharf said.

"Senate funds for Senate-related work," Bayne said

"Correct," she said.

On Tuesday, Neubauer had Scharf review a series of travel claims she had filled out for Duffy.

Scharf testified, as did Mercer before her, that Duffy had pre-signed blank travel claims for efficiency and expediency. But Scharf, who has worked in a number of parliamentary offices, including those of two prime ministers, said this was also a common practice on Parliament Hill.