The amiable demeanour of the former Conservative — once the Harper government's point man on defending the Tories against charges of voter fraud, now an Independent MP who faces Election Act charges of exceeding campaign spending limits — fell away under the heat of a day-long grilling on the witness stand.
"Your assertion is offensive," Del Mastro told Crown lawyer Tom Lemon, angered by the suggestion that he'd engaged in prolonged contract negotiations with a data-consulting firm in hopes of recouping the cost of a software program he claims never worked.
Del Mastro is charged with overspending during the 2008 federal election campaign, failing to report a personal contribution of $21,000 to his own campaign and knowingly submitting a falsified document. He has denied all the allegations.
In the course of methodically challenging Del Mastro on a series of points, Lemon took Del Mastro back to a series of emails the MP has flatly said are fake.
They detail alleged discussions between Del Mastro and Frank Hall, president of the now-defunct Holinshed Research, whose work on the 2008 campaign forms the bedrock of the Elections Act charges.
Hall has testified that his company provided hundreds of hours of voter identification calling services for Del Mastro, for which the MP paid him with a personal cheque — a payment which would have put him over his campaign spending and personal contribution limits.
Hall has also said he backdated invoices at Del Mastro's request so that his firm's services would be billed outside the campaign period.
But Del Mastro has repeatedly told the court he never engaged Holinshed for voter identification services during the 2008 campaign, despite Hall trying to convince him to do so.
Instead, he said he used Holinshed during the campaign only for a portion of get-out-the-vote calling services on election day.
He has said he did pay Hall with a personal cheque, but that was for a deposit for riding mapping software called GeoVote, to be shared by Del Mastro's constituency office and the Peterborough Conservative Electoral District Association.
GeoVote never ended up performing as intended, Del Mastro testified, and he eventually terminated his relationship with Holinshed after Hall repeatedly failed to deliver what was promised.
The Crown took Del Mastro back to the email chain in which the MP severed his ties with Hall, which prompted the Holinshed president to reel off the alleged numerous concessions he had made for Del Mastro, which included backdating invoices.
"You didn't deny them. You had an opportunity," Lemon said of Hall's assertions.
"No sir," Del Mastro said, raising his voice.
"Long before any investigation, you had an opportunity in this response to correct Mr. Hall with anything he was saying that was incorrect, and you did not," Lemon continued.
"I did not correct it, because it was not said, sir," Del Mastro replied firmly.
Del Mastro added that while he did have an email exchange with Hall to end their ties, he suggested Hall's message in that chain had been tampered with.
The exchange between Del Mastro and Lemon grew even testier as the Crown prosecutor put forward a theory which appeared to catch the MP off guard.
It was based on an exchange of documentation that took place between Hall and Del Mastro after the 2008 election over GeoVote and other Holinshed software.
The trial has heard that after GeoVote didn't seem to work, the Peterborough Electoral District reimbursed Del Mastro a portion of the $21,000 personal payment which he had given to Holinshed as a deposit for the software.
But, court has heard, Del Mastro was still left with having paid about $9,000 for a program that never got used.
"Sir I suggest to you that these different manifestations of the 2009 contracts, quotes, invoices ... that the back and forth between Frank Hall and you ... that these were all an effort by you to recover the $9,000 you were out," Lemon said.
"What you're suggesting is false. I was not trying to recover money," said Del Mastro, growing increasingly irate.
"The bottom line is that your're still out $9,000," Lemon pressed.
"If it was as simple as submitting this for payment, that I was seeking to somehow take money from the taxpayer, that I was not owed, why did I not do it?" Del Mastro retorted.
"I did not do that. And I could have, I could have. But I did not. That's the answer to your assertion, sir," he said, thumping down a booklet of evidence on the witness stand for emphasis.
If found guilty, Del Mastro could face a fine of $1,000 and a year in jail.
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