Both the Tories and New Democrats say they want to know what's been going on since the OPP started their criminal investigation of Ornge a year ago.
"It's been a year, we haven't heard a peep out of them," said NDP health critic France Gelinas.
"When all you have is silence ... you tend to assume the worst."
The all-party committee probing the Ornge fiasco has the right to know how the investigation is going, said Tory Frank Klees.
Both Gelinas and Klees said they're not looking for any details that could jeopardize the case, they just want some reassurance.
"But it's been many months," Klees said. "We want to know how seriously the OPP is pursuing the actions of a number of people in this organization."
Lewis is expected to appear before the committee on March 20, but the date hasn't been confirmed yet, said OPP spokesman Sgt. Pierre Chamberland.
The evidence gathered must be able to stand up in court, so they have to be very careful, he said.
"It's unfortunate that the commissioner is being called to testify or we have to talk about it before we are able to complete an investigation," Chamberland said.
"But that's what we have to do, so that's what he'll be doing."
The committee has heard explosive testimony about an alleged kickback scheme, exorbitant salaries and badly designed medical interiors in brand new helicopters. Ornge receives about $150 million a year from the province.
The recent arrest of the head of an Italian company linked to Ornge is another reason why the OPP need to provide an update on the case, Klees said.
Finmeccanica CEO Giuseppe Orsi is under investigation in a case involving the payment of bribes in the US$670-million sale of 12 helicopters to the government of India.
It's "uncannily parallel" to the $144-million deal helicopter-maker AgustaWestland, a subsidiary of Finmeccanica, signed with Ornge for 12 helicopters, Klees said.
Agusta paid an Ornge spinoff company $6.7 million after it reached the deal, which included a $4.7-million agreement for marketing services.
Ousted Ornge chief executive Chris Mazza said the extra fees were not part of a kickback scheme and Agusta has vehemently denied any wrongdoing.
"I want to know from the OPP commissioner, have they called in the RCMP?" Klees said.
"It's been a long time and we're hoping to at least get some confirmation from the commissioner that no stone will be left unturned."
He said he also wants to know what the governing Liberals are doing to recover funds from Ornge's spinoff companies.
Documents tabled with the committee show Mazza assigned a $10-million life insurance policy for himself, Klees said.
The policy appears to be under the control of one of Ornge's for-profit companies, along with $450,000 meant to pay the premiums, he said.
"The question we have is what has happened to that," Klees said.
If the money is still there, the government should go after it, he added.
Health Minister Deb Matthews said she's instructed Ornge to do whatever they can to recover "any inappropriate expenditures."
"I'm sad to say that nothing shocks me anymore when it comes to Chris Mazza," she said.
Auditor general Jim McCarter found that Ornge received $730 million from the Health Ministry over five years — and borrowed $300 million more — with virtually no government oversight.
Other documents tabled with the all-party committee showed that Mazza received $1.2 million in loans in a single year, in addition to his high salary.