At the mid-point of a heated election campaign, the B.C. criminal justice branch has confirmed that a New Democrat MLA has been investigated for allegations of spousal assault.

The allegations against MLA Doug Routley stem from incidents in 2006 and 2007 and were reported to police in November 2008. They were investigated last December.

It's the latest foray into the political muck in B.C., where the Liberals and New Democrats are battling for votes in the May 12 provincial election.

A special prosecutor was appointed to the case -- routine when politicians come under police scrutiny -- and concluded the Vancouver Island MLA would not face any charges.

In a statement released by the criminal justice branch Thursday after the allegations surfaced in the campaign, special prosecutor Michael Tammen, a Vancouver lawyer, said there was no confirmatory evidence available to the RCMP or himself.

The statement pointed out that more than six months had elapsed since the last alleged incident.

"It could not be said that there was a substantial likelihood of conviction," said the statement.

"Further, given the passage of time, it could not be said that it would be in the public interest to proceed with any charges by way of indictment, which would have been required given the six month limitation period for summary conviction proceedings."

The Crown noted that Routley, who is embroiled in a divorce dispute that began in September 2008, met with police and denied the allegations.

New Democrat Leader Carole James only found out about the investigation at the end of March and only learned about a special prosecutor's involvement a few days ago.

She agreed she should have been told earlier, but said she understands the reasons behind the silence from Routley.

"Doug's lawyer said to him that he shouldn't release the issue of a special prosecutor to try and protect the interest of a young child. I completely understand that."

The allegations that surfaced against Routley are the latest in a series to be trotted out by both main political parties over the first few weeks of the campaign.

Abbotsford Liberal MLA John van Dongen resigned his solicitor general and public safety minister cabinet post after revealing his driver's licence was suspended earlier this month over speeding tickets.

Van Dongen took over the job from John Les, who resigned last year after it was revealed he was being investigated by a special prosecutor.

James said this investigation is different from the situations of both Les and van Dongen who both resigned as solicitor general

"That's someone whose job it is to uphold the law," she said.

"It seems like a very clear distinction. Now I understand the Liberals are going to continue to push this, that's no surprise to me."

Vancouver New Democrat candidate Ray Lam quit the campaign after photos from his private Facebook page were made public, one showing him with his hand on a clothed woman's breast and another of him in his underwear with his pants around his knees.

Liberal candidate Marc Dalton had to apologize for remarks he made about homosexuals in a 1996 email in which he suggested homosexuality is a lifestyle choice comparable to adultery, gambling and pornography.

The driving records of other Liberal and New Democrat candidates have also been revealed during the campaign.

Routley, who is seeking re-election in the North Cowichan-Nanaimo riding, was not immediately available for comment.

Dirk Meissner reports for The Canadian Press.