The Progressive Conservative party is raising concerns about new voting technology that will be used to cast and count ballots in Ontario's provincial election, CBC News has learned.

The June 7 vote will be the first general election in Ontario to use the electronic voting machines. The technology includes devices than scan voter cards and tabulate marked ballots.

The provincial agency overseeing the vote worked frequently with all the major parties over the past three years to test and demonstrate the reliability and security of the new technology. However, since Doug Ford won the PC leadership in March, the party has contacted Elections Ontario multiple times with questions and concerns.

The PC party lawyer, Arthur Hamilton, wrote to Elections Ontario this week to flag several issues, including concerns about protection from hacking and the certification of the vote-counting machines.

Ontario Chief Electoral Officer Greg Essensa holds up a printout of a mocked up vote result from a vote tabulator as he demonstrates an electronic voting machine. (Chris Young/Canadian Press)

In separate letter dated May 17, PC officials accused Elections Ontario of providing the party with inadequate information about the vote-counting equipment. The officials asked for a private briefing on the new technology, but Elections Ontario refused to grant such a meeting during the campaign period.

"Among the 28 parties, there's a very high level of confidence in the technology and we have had very few concerns raised at all," said Deborah Danis, chief administrative officer of Elections Ontario

"Integrity is the cornerstone of our organization," Danis said in a phone interview Thursday. "We have the utmost confidence in this technology."

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The PC party declined to provide CBC News with more information about the party's issue with the voting machines. "We'll address any concerns on these matters directly with Elections Ontario," said PC spokesperson Melissa Lantsman.

Both the Liberal Party and the NDP say they have no concerns about the technology.

"The week before an election is not the time to be raising a complete red herring,`said Jack Siegel, lawyer for the Liberals.

Elections officials man a polling station during the Ontario provincial election at a Mississauga voting station in 2007. (J.P. Moczulski/Canadian Press)

He said challenging the integrity of the vote "has the potential to be exceptionally damaging to the democratic system and to the confidence of the people of Ontario in an election system that has been thoroughly discussed and tested."

An NDP spokesperson says Elections Ontario has provided all the parties with detailed information about the voting process and the counting machines.

Danis said she cannot comment on the nature of the concerns raised by the PCs, nor would she confirm whether the party has filed a formal complaint to Elections Ontario.

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She defends the security of the voting machines.

"There is no possibility that the counts could not be fully corroborated," said Danis. "I would actually argue that the introduction of technology increases our accuracy."

The paper ballots are kept in case any issues or disputes arise, Danis said.

In April, after the dust had settled on the PC leadership race, Elections Ontario gave party officials a half-day briefing about the technology.

Danis refers to the briefing in a May 22 letter she wrote on behalf of the chief electoral officer, in response to the PCs.

"We have provided numerous occasions to all parties to learn about the technology, ask questions and even actively participate in using the equipment," writes Danis in her letter, a copy of which was obtained by CBC News.

"All political parties have been actively involved in our modernization process," she writes. "Progressive Conservative Party officials and representatives have actively participated in our key events leading up to this general election."