Del Mastro, a former parliamentary secretary to Prime Minister Stephen Harper, was convicted last fall of violating the Canada Elections Act during the 2008 election. He has since resigned his House of Commons seat.
At what was supposed to be a sentencing hearing Tuesday in Peterborough, Ont., Crown lawyer Tom Lemon announced that Del Mastro's attorney had filed an application for a mistrial.
Lemon called the move an attempt to appeal the judgment in the case and sought to have the application dismissed.
"The trial is finished. Mr. Del Mastro doesn't get a do-over because he doesn't like the result," Lemon told Justice Lisa Cameron, who has presided over the case. "There's nothing to suggest he didn't receive a full and fair trial."
Del Mastro failed to show that new arguments in the mistrial application are any different from those made at trial, Lemon said. Even if they were, why were they not made during the trial, he asked.
"Your Honour should not be put in the untenable position of standing in judgment of your own position and deciding whether you were right," he said.
Del Mastro defended his mistrial application by saying he was simply seeking to have the law applied "the way it's intended to."
"Nobody wants this over more than I do," he said outside court.
Del Mastro was found guilty of exceeding spending limits, failing to report a personal contribution of $21,000 to his own campaign and knowingly submitting a falsified document.
He faces a maximum penalty of one year in jail and a $2,000 fine on each of the three convictions.
The mistrial application was brought by Del Mastro's new lawyer, Leo Adler, who was hired after Cameron delivered her judgment. That in itself is an issue, Lemon argued, as Adler didn't have transcripts for every bit of testimony heard at trial.
"There has to be finality to these proceedings," Lemon added.
"What Mr. Del Mastro's application boils down to is an argument that this court was wrong in convicting him and incorrect in deciding the legal and factual issues as it did. In my submission, that is an application for an appellate court."
Adler countered that his mistrial application was valid.
"Natural justice, with the greatest of respect, means Your Honour does have the obligation of hearing this application," he told Cameron.
Adler's arguments centred on a contract between Del Mastro and a now defunct data-consulting firm whose voter identification and get-out-the-vote calling services had pushed the former MP over his campaign spending limit.
"Your Honour, with respect, never states that contract was completed. Certainly not completed in full. If it was completed in full, yes, the money was over ... and there's nothing to argue," Adler said.
"Because you didn't say that, one is therefore left with a missing element."
Cameron noted that the prosecution's case was not about whether a particular contract was completed.
"It was about exceeding election expenses. The contract is perhaps a reflection of that," she said.
Adler suggested that the commercial value of the contract was different from the $21,000 Del Mastro was found guilty of overspending.
Lemon countered that the element of commercial value only applied to something with non-monetary value.
"Mr. Adler argues that we have to determine whether work was done. No, no, you have to determine whether cost was incurred," he said.
Cameron has yet to rule on whether she will allow the case to be re-opened. The case returns to court on Feb. 19.
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