TORONTO -- The Progressive Conservatives asked the speaker of the Ontario legislature to find Hydro One in contempt Tuesday after the ombudsman said the giant utility misled the government about its billing problems.

"Misleading the house is a charge that I don't make lightly, and I take the likelihood that Hydro One may have intentionally misled the house very seriously," PC house leader Steve Clark told the legislature. "The behaviour shown by Hydro One, as documented in the ombudsman's report, could amount to contempt of this legislature."

Ombudsman Andre Marin issued a special report Monday accusing Hydro One of lying to his officials and to the government about the scope of billing problems created by its new computer system.

"They obstructed and lied to the minister of energy's office, the board of directors and the Ontario Energy Board," Marin said as he released his report.

Clark admitted Hydro One didn't directly mislead the legislature, but said the Crown agency still misled MPPs who had asked the ombudsman to investigate complaints from constituents who were hit with huge electricity bills.

"While the statements were not made in the house or in committee, they were made to mislead the minister's office, which was relaying that misleading information to this house and members of the legislative assembly," he said. "We were trying to get answers and we were being blocked, deceived at every step.

Six months after the utility became aware of the serious nature of the billing problems affecting up to 100,000 customers, Hydro One's CEO gave government the impression that the issue was minimal, added Clark. Everyone at Hydro One seemed to be downplaying the seriousness of the billing errors, he said.

"While specifically misleading statements were made by several officials at Hydro One, it was truly, in my opinion, a systematic response to all issues designed with an intent to mislead," said Clark.

The Liberals insisted Hydro One never mislead the legislature and asked Speaker Dave Levac to dismiss the contempt charge.

Levac said he would make his ruling later.

In his special report, Marin said Hydro One treated customers "abominably" after being flooded with complaints about billing mistakes, and accused the Crown corporation of lying about the extent of the problems. Marin rejected the idea of pursuing charges against anyone at Hydro One, even though misleading the ombudsman could result in fines or even a jail term.

"We'd have to build a new courthouse because there are a lot of people that you'd have to charge," he said. "I'm simply reminding Hydro One not to do it again."

Hydro One CEO Carmine Marcello insisted his officials never lied to anyone about the extent of the billing problems.

The New Democrats agreed with the Tories on the contempt issue, but said they wanted to stay focused on trying to block the Liberals plans to sell 60 per cent of Hydro One to private investors. The ombudsman will lose oversight of Hydro One once the budget bill allowing the sale is passed by the legislature.