Finance Minister Ralph Goodale says he will not step down during a criminal investigation into an alleged leak of an announcement on income trust taxation rules.

"It's very clear from the comments of the RCMP that they have no information, no evidence, no indication of any wrongdoing on my part and no direct allegation against me personally,'' Goodale told reporters Wednesday at his constituency office in Regina.

"I'm very anxious to make sure that my reputation for integrity is absolutely vindicated, because that is a very crucial part of who I am and what I stand for -- that's been my modus operandi for over 30 years.''

Goodale promised full co-operation with the investigation.

Word of the investigation came out after the NDP received a letter from RCMP Commissioner Giuliano Zaccardelli dated last Friday indicating the Mounties would proceed with an investigation into the affair.

On Nov. 23, Goodale announced there would be no change in the tax rules governing the investment vehicle, although he did cut personal income taxes on corporate dividends.

In the hours before the announcement, a spike in trading of income trusts occurred on the Toronto Stock Exchange.

Back on Nov. 28, Judy Wasylycia-Leis, the NDP's finance critic, requested the RCMP review the announcement and see if any finance department staffers tipped off any Bay Street insiders.

"I'm both floored and pleased that our inquiry to the RCMP had produced something, and we'll now be able to get to the bottom of the income trust case file and Canadians will be able to know what happened," Wasylycia-Leis told CTV Newsnet on Wednesday.

She wants Goodale, one of Prime Minister Paul Martin's top ministers, to step aside from his cabinet position until the matter is resolved.

"I really believe it is incumbent on the minister of finance, Ralph Goodale, to step aside while this criminal investigation is underway," said Wasylycia-Leis.

"It just seems to me that when you're dealing with something this serious in a department for which he has complete and full responsibility, that the onus is on Ralph Goodale is to step aside and let the investigation proceed under the RCMP."

The Liberal Party said it would study the RCMP announcement before commenting, although Veterans Affairs Minister Albina Guarnieri said, "Ralph Goodale has impeccable integrity and I attribute all this to very nasty noise from the opposition."

Political impact

Opposition parties have been keen to make hay over the issue, suggesting the stock movements show Liberal-friendly investors must have received tips from sources within the federal government.

Conservative MP Jason Kenney asked Wednesday: "Who knew what in the PMO about this decision on income trusts?"

Corruption is also a major election theme, given the sponsorship scandal.

The Conservative Party has tried to further the income trust case by filing a complaint with the Ontario Securities Commission.

The commission has yet to say whether it's acting on the complaint. Wasylycia-Leis has also sent the OSC a letter.

While the RCMP is investigating, that doesn't necessarily guarantee there will be criminal charges.

Some market watchers have suggested that Goodale didn't have many policy choices before him. The one he did choose was the most politically acceptable course.

As a result, it would be easy to guess which way Goodale would have gone in his announcement, they say.

However, forensic account Al Rosen said Nov. 30, "My gut feel is there was a leak."

CTV found at least one group, the Canada's Association for the Fifty Plus (CARP), was told an announcement was coming, although the group wasn't provided with details.

There were also e-mails and postings in various online forums suggesting an announcement was coming that would involve cutting dividend taxes. The wording in the correspondence was similar to that used by Goodale in his actual announcement.

However, one analyst, pollster Tim Woolstencroft of The Strategic Counsel, said regardless of what an investigation turns up, it again points the spotlight on the Liberals' weak point -- ethics.

"When ethics have been a problem over the last 18 months, we've seen Liberal support decline," he said.

With a report from CTV's Roger Smith