Senator David Tkachuk says he never advised Mike Duffy about housing expenses

A senior Conservative senator who was labelled as the guru of Senate rules by Mike Duffy's judge says the widely held view of his role in the whole affair is more fiction than fact.

Sen. David Tkachuk insists he never advised Duffy on questions about his housing and travel allowances, despite Duffy's criminal trial having been told otherwise.

Tkachuk says the only advice he gave during a January 2009 meeting of new senators was about caucus responsibilities, since he hadn't yet been appointed to the executive of the Senate's internal economy committee, which oversees expense rules.

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Tkachuk wasn't called to testify at the trial and he says the Crown never contacted him, even though he was available to take the stand.

He says the facts in the criminal trial skewed his role in the matter and is speaking out to give his side of the story.

Duffy returned to Parliament Hill for the first time Monday since being acquitted of 31 criminal charges on fraud, breach of trust and bribery related to his Senate expenses.

Today markshis first chance to take his seat inside the upper chamber and face colleagues who voted to suspend him without pay in late 2013.