The mysterious third party who uncovered serious allegations that led Prime Minister Stephen Harper to toss MP Helena Guergis out of caucus is a private investigator, CTV News has learned.

Police sources say the licensed private eye contacted a Conservative Party lawyer in Toronto, and expressed concern about a potential threat of blackmail arising from allegations about the purchase and use of drugs.

It has not been confirmed who may have purchased or used the drugs in question, or who may have been prone to blackmail.

When the lawyer received the information, he immediately alerted the prime minister.

Guergis was ejected from the Conservative caucus last week. Harper asked the RCMP to consider an investigation based on what he called "serious allegations." The substance of those allegations remains a mystery.

On Monday, Transport Minister John Baird said the allegations "came forward from a third party." He said the alleged misdoings "do not involve any minister, any MP, any senator, or for that matter any government employee."

Guergis email to CTV

Guergis has maintained any allegations against her are "baseless."

In an email to CTV, Guergis said she is unable to fully answer questions regarding the allegations against her at this time.

"I'm sure you can appreciate it is very difficult to answer allegations based on innuendo from anonymous sources. Nevertheless, I intend to defend myself to the fullest extent to ensure that the record is set straight," Guergis wrote.

"What I can tell you is that as soon as I heard the Prime Minister had referred certain matters to the RCMP and the Ethics Commissioner I contacted both parties to offer my full cooperation. The Ethics Commissioner has already said she does not have any information to warrant an investigation and I'm still awaiting an answer from the RCMP. Because this is now in the hands of the police I have retained legal counsel."

The private eye was investigating businessman Nazim Gillani and Mike Mihelic, a former Toronto Argonaut who works for Gillani. Both men are facing fraud charges on an unrelated matter.

Gillani has claimed to his associates that Jaffer, who is a partner in green energy consulting firm Green Power Generation Corp., could give them special access to the Prime Minister's Office, a claim that Harper has refuted.

Patrick Glemaud, Jaffer's partner at GPG, said his company has never lobbied government on behalf of Gillani.

Glemaud said Tuesday that while he had met on two occasions Gillani, his company was only asked to look into whether a specific green technology would be viable in the current marketplace.

"There was no business transaction (to) ever take place between GPG and Mr. Nazim Gillani or his company," Glemaud told CTV's Power Play. "There was no exchange of funds, there was no contract whatsoever, there was no lobbying activities taking place by GPG on behalf of any clients whatsoever."

Glemaud's comments were in response to a letter the Liberals sent Monday to the federal lobbying commissioner, asking her to investigate Jaffer's business dealings.

In the letter, Liberal MP Marlene Jennings asked Lobbying Commissioner Karen Shepherd to launch an investigation "into possible violations of the Lobbying Act involving GPG -- Green Power Generation Corp and its representatives."

According to an article published April 8 in the Toronto Star, Jaffer told a group of business associates, including Gillani, during a meeting last September that he could help them obtain government funds for business projects. In particular, he allegedly said he had access to "a green fund."

The government denies Jaffer has any special access to government or government funds.

Glemaud said Tuesday that the Liberal Party's allegations against him, Jaffer and their company are "untruthful," and said "at no time did we submit a government grant application whatsoever on behalf of anyone."

Glemaud also denied that Jaffer ever used a government office to conduct business on behalf of GPG.

Glemaud accused the Liberals of launching a smear campaign against him, but also said he would send his own letter to the lobbying commissioner to say he would co-operate with any investigation she may launch.

Ethics commissioner won't investigate Guergis allegations

Earlier Monday, the Commons ethics commissioner said she will not investigate former cabinet minister Helena Guergis, Jaffer's wife, based on allegations forwarded by the PMO.

Mary Dawson said Tuesday that based on the information she has, she's not in a position to proceed with an inquiry.

She offered no further details because of privacy concerns.

Dawson noted that if the RCMP begins an investigation, as Prime Minister Stephen Harper has requested, her office would be required to suspend its own investigation anyway. But she added she would continue to monitor the situation.

The reviews normally conducted by Dawson's office fall under either the Conflict of Interest Code for Members of the House of Commons or the Conflict of Interest Act.

Opposition reaction

During question period in the House of Commons Tuesday, NDP Leader Jack Layton renewed the opposition parties' calls for specific details about the allegations that got Guergis kicked out of caucus.

"Here's the so-called tough-on-crime prime minister who won't even tell Canadians why he's called the cops on one of his own," Layton said. "Why are the Conservatives afraid to tell Canadians the truth?"

Conservative MP Mike Lake, parliamentary secretary to the industry minister, defended the government's silence on the issue.

"It would be completely irresponsible for the Prime Minister's Office to put forward allegations out for public debate," Lake told Power Play. "It would be completely unfair to the parties involved, you wouldn't do that."

Liberal MP Martha Hall Findlay said Canadians have the right to know "if rules have been broken."

"The truth needs to be found," Findlay told Power Play.