LONDON, Ont. -- London Mayor Joe Fontana says in retrospect it was "stupid" of him to alter a document he submitted for expenses while he was a Liberal member of Parliament, but insists it was no forgery.

Fontana took the stand Wednesday in his own defence after pleading not guilty to fraud, breach of trust and uttering forged documents from his time as a cabinet minister.

He admitted making seven changes -- including whiting out his wife's signature and replacing it with his own -- to an existing contract for a hall rental for his son's 2005 wedding to reflect an event he planned for then-finance minister Ralph Goodale at the same venue.

Other alterations on the contract were changing the date of the event from June 25, 2005 to Feb. 25, 2004, the word "wedding" to "reception" and the addition of a yellow sticky note saying "misc constituents reception."

The event didn't end up going ahead at the Marconi Club, but Fontana believed the club was owed a $1,700 deposit from his MP budget. Since he had only spoken with the club's president over the phone and didn't have any paperwork, Fontana changed several details on the wedding contract from a few months prior and submitted it, he testified.

One of the changes was to write the word original in quotation marks at the top of the document.

"I took a document that I thought was null and void...put 'original' there so it wouldn't be confused with anything else," Fontana said.

During a testy cross-examination, Fontana used various terms to describe what he did to the contract -- modified, changed, altered, and his most common refrain, that he just created a new document -- but he bristled at Crown attorney Timothy Zuber's suggestion that it was a forgery.

"Yeah, excuse me?" Fontana said after his lawyer objected. "Dumb, stupid, yes. I was busy, it was available...Things were harried at the time in Ottawa -- a minority government."

Zuber asked Fontana why he wouldn't have just gone to the Marconi Club and asked for an invoice that he could submit.

"I submitted that document as proof," Fontana replied.

Zuber wondered if there were any other occasions in which third-party service providers for MP functions didn't provide him with a bill.

"Well no, because they wouldn't be paid," Fontana said.

"My point exactly," Zuber replied.

A $1,700 Government of Canada cheque was ultimately sent to the Marconi Club, where it was listed on their books as payment for Fontana's son's wedding.

The court has heard conflicting evidence about whether government officials had been instructed to reimburse Fontana or the Marconi Club the $1,700. Fontana insisted it was intended for the club, but the Crown suggested otherwise.

Zuber suggested that Fontana didn't intend for the Marconi Club to put the money toward his son's wedding, but that the cheque was supposed to be sent to him to "line your pockets with $1,700 cash." Fontana disagreed.