06/01/2015 05:00 EDT | Updated 05/31/2016 05:59 EDT

Mike Duffy Trial: Key Witnesses Still To Come In Trial Of Suspended Senator

After a three-week hiatus, the Mike Duffy trial resumes in Ottawa in a case that has so far included delving into the minutiae of Senate administration rules, scrutinizing the workout habits of the suspended senator and examining the purchase of his dog.

But the 23-day-old trial, which began on April 7 in the Ontario court of justice, has yet to hear from important witnesses, including other senators, Duffy's business associate Gerald Donohue, Prime Minister Stephen Harper's former chief of staff Nigel Wright and Duffy himself.

Lawyers are expected to spend the first few days back arguing over whether details of a 2013 internal Senate audit on the residency status of senators are admissible — the type of side issue that has helped extend the length of the trial and left it unclear who will testify in this second portion of the case.

The case, being heard by Judge Charles Vaillancourt, had been slated for 41 days, but both the Crown and defence made it clear during the trial they would need more time. The second part of the trial is scheduled to end June 19, before resuming yet again at some undisclosed date.

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 Wright.

Bribery charge

While the bribery charge has grabbed the most headlines, it has barely been mentioned.

Instead, Crown prosecutors Mark Holmes and Jason Neubauer spent the first 22 days slowly building their case, alleging Duffy committed fraud and breach of trust (a charge specific for parliamentarians) by willfully ignoring Senate rules and claiming expenses for services that served no parliamentary function.

Mike Duffy trial: Links to key documents

Court has heard from top Senate administrative officials who have, in painstaking detail, gone over those rules. The Crown has also spent time establishing that some of Duffy's expenses were paid through his friend Donohue, who had been awarded a series of Senate research contracts with Duffy worth nearly $65,000.

The RCMP has said Donohue received the money for "little or no apparent work."

For its part, the Crown alleges that pool of money was used by Duffy to pay for some inappropriate or non-parliamentary services — expenses, the Crown believes, that wouldn't have been covered by the Senate.

Witnesses who testified they received these cheques said they had no earlier dealings with Donohue, with most saying they had never heard of him.

Court has heard that some of the expenses claimed by Duffy and paid through Donohue included more than $10,000 for workout sessions with a personal fitness trainer, $300 for makeup and costs for personal photographs.

Travel expenses

The Crown has also zeroed in on a series of Duffy's travel expenses they allege were claimed for partisan fundraising events. Some Conservative MPs have testified that Duffy, a popular draw, was asked to and agreed to participate in such political events.

However, the travel expenses in question also include $3,000 to deliver a speech and a claim of $698, which the Crown alleges was for a trip Duffy took with his wife to a dog show in July 2010 to buy a Kerry blue terrier.

Duffy's lawyer Donald Bayne spent days cross-examining some Senate administrative officials, poring over Senate rules with those witnesses, arguing the regulations Duffy is accused of contravening were unclear and ambiguous.

Bayne has not denied Duffy paid some of his expenses through Donohue, but he has suggested that such an arrangement, while "administratively irregular," was certainly not criminal. He has also driven home the point that none of the witnesses who were paid by Donohue were told to keep quiet about the arrangement, and that none offered any kind of kickback to Duffy.

Fitness project

Bayne has suggested that the expenses in question were all allowed under the rules laid out in Senate guidelines, and all legitimate part of parliamentary functions, including for the personal fitness trainer who Bayne said was consulting with Duffy on a seniors fitness project.

Bayne has defended the travel expenses, arguing the Senate administrative rules explicitly state that partisan activities are an essential part of a senator's duties, adding that nowhere in those rules does it define the term "partisan."

He has also argued that many of these so-called fundraising trips were tied into other government-related business, such as providing information on the government's economic action plan.

And as for the dog? Well, Bayne argued, Duffy never purchased a dog at the Peterborough, Ont., dog show, but instead bought a dog from a New Brunswick breeder.

Also on HuffPost

Photo gallery Mike Duffy Trial: Artist's Sketches See Gallery