06/07/2013 02:22 EDT | Updated 08/07/2013 05:12 EDT

NDP want McGuinty to testify under oath about deleted emails

The Ontario New Democrats are calling on former premier Dalton McGuinty to testify under oath about the deleting of emails by his former chief of staff and other high-ranking Liberals.

Peter Tabuns, the NDP's energy critic, says McGuinty must appear before the justice committee hearings into cancelled gas plants in Oakville and Mississauga to explain why emails on the two projects were permanently wiped.

Tabuns says if McGuinty won't testify before the committee, then Premier Kathleen Wynne should force him to show up to keep her promise of being open and transparent.

- Dalton McGuinty admits moving gas plants was his decision

McGuinty testified before the committee in early May. His office said he was not available to comment on the NDP's request for him to reapear.

A report released earlier this week by privacy commissioner Ann Cavoukian says McGuinty's chief of staff, David Livingston, inquired up until January on how to permanently delete electronic records from government databases.

There are no penalties for violating Ontario's Archives and Recordkeeping Act, but Cavoukian's findings could help the opposition parties find the Liberals guilty of a rare contempt of parliament motion, which can carry legal sanctions.

- Ontario Tories want police to probe Liberal gas plant email deletion

Opposition parties say the deleted emails confirm their earlier claims that the Liberals were trying to hide the true costs of cancelling the gas plants, which is now an estimated $535 million, well over the $230 million the government had claimed.

The Progressive Conservatives, meanwhile, said they have asked the Ontario Provincial Police to investigate the matter as theft of government property.

Premier Kathleen Wynne said on Thursday that the mass email deletions were unacceptable and staff have been made aware of their record retention obligations.