OTTAWA -- An aide to Senate Speaker Leo Housakos says it was known around the corridors of the upper chamber that staff took shortcuts when they filed travel claims for senators.

Loren Cicchini is the second veteran Senate staffer to tell Sen. Mike Duffy's trial that senators would regularly pre-sign travel claim forms before they were filled in and submitted to financial administrators.

Duffy has pleaded not guilty to 31 charges of fraud, breach of trust and bribery, several of them in connection to trips he took while claiming to be on Senate business.

Cicchini doesn't submit such expense claims for Housakos in her current role as parliamentary affairs adviser, but did so for former Conservative senator JoAnne Buth for about a year and for retired Progressive Conservative senator Michael Meighen for more than 20.

She said she never told Senate finance what she was doing.

"I was never asked, nobody was ever asked and it's not something that I would have volunteered because I was aware that it's not right to pre-sign something," Cicchini testified under Crown questioning.

"It was an agreement between senator Meighen and myself. He trusted me, and it was a matter of trust."

Last week, former Duffy assistant Diane Scharf testified that pre-signing forms was common practice in the office, as a means of saving time.

Cicchini said she can't pinpoint how she found out about the practice, but just that it was something that people talked about.

"It's like rumours. You hear it. You don't know where it comes from and you don't know exactly where you heard it," she said under cross-examination.

The Crown's main objective by calling Cicchini as a witness was to undermine the testimony of another Duffy assistant, Melanie Mercer.

Mercer had told the court last week that Cicchini and another Conservative assistant were specifically assigned to shadow her when she was starting out, and show her the ropes. One of the pieces of advice Mercer said she got was to get expense claim forms pre-signed.

Cicchini worked in a Parliament Hill office next to Duffy's and said she remembered often answering questions for Mercer. But she said she was never asked to train her, nor does she remember being in a conversation about pre-signing the forms.

It's unclear whether the recent testimony on the creative Senate office practices will help or hurt Duffy. On the one hand, the Crown could paint a picture of a system where Duffy and others abused the public's trust.

On the other hand, it could bolster Duffy's defence that while he might have taken part in administrative irregularities, it doesn't amount to criminal behaviour.

The court is expected to hear from forensic accountant Mark Grenon on Tuesday. He is the Crown's expert witnesses on the money trail around Duffy's expenses.