Suspended senator Patrick Brazeau is attending the trial of Mike Duffy, his former Conservative colleague.
Brazeau is sitting in the back of the courtroom, taking copious notes on a pad of lined yellow paper.
Outside the courtroom, he said he's on hand to support Duffy, who is facing 31 counts of breach of trust, fraud and bribery.
Brazeau himself faces one count each of fraud and breach of trust related to his own disputed travel and living expenses.
He may be interested in the arguments Duffy's lawyer is making – that the Senate rules offer no specific criteria for what constitutes a primary or secondary residence.
Duffy filed $82,000 in living expenses for a home in suburban Ottawa, while declaring his primary residence was in Prince Edward Island, where he spent significantly less time.
Defence lawyer Donald Bayne kicked off Day 3 of the trial by continuing his cross-examination of former Senate law clerk Mark Audcent.