Former Manitoba Conservative MP Vic Toews is being investigated over a possible violation of conflict-of-interest guidelines — something NDP MP Pat Martin said is necessary "to uphold the integrity of our parliamentary institutions."

The federal office of the Conflict of Interest and Ethics Commissioner says there is enough information to examine whether Toews's lobbying efforts for Peguis First Nation violated the rules. Toews had significant dealings with the Manitoba First Nation while in office.

The conflict question was raised to the office by Martin, who represents Winnipeg Centre.

"It's a fundamental principle that you're not supposed to use your time in office for personal or private gain ... that includes your lobbying activities post-employment as a former cabinet minister," Martin told CBC News Thursday.

"It just doesn't meet the smell test for a lot of Canadians that a cabinet minister should be able to benefit from their time in public office for personal or private gain. If that's the case, we want the ethics commissioner to not only tighten up on this case but perhaps recommend changes to the rules so it can't happen in the future."

CBC News reported last week that within months of leaving cabinet, Toews, the former treasury board president, met with with a lawyer representing Peguis First Nation on several occasions regarding a settlement of the Kapyong barracks, according to court documents.

The old military base on Kenaston Boulevard in Winnipeg has sat empty since 2004, tangled in court proceedings. First Nations want to claim the land under treaty entitlements.

Conflict-of-interest rules prohibit former cabinet ministers from giving advice on or consulting about confidential information they found out while in government.

"There's a two year cooling off period for a minister, especially a senior minister like Mr. Toews, [where he's] not supposed to have contacts that benefit he or his family personally stemming from his activities as a public office holder," said Martin.

Martin sent a letter to the ethics commissioner Mary Dawson outlining his concerns about Toews.

In her written response, Dawson told Martin, "I have reasonable grounds to commence an examination."

Martin said he was glad with Dawson's response, adding he hopes "everybody involved will co-operate fully."

Toews has since filed a counter suit with the ethics commissioner against Martin.

"I was a little taken aback when Vic Toews ... reported me to the ethics commissioner for reporting him to the ethics commissioner," said Martin. "It seems like a rather petty game of tit-for-tat.

"We're just trying to uphold the integrity of that code. I don't apologize for filing this report to the ethics commissioner. I have a duty and an obligation to uphold the integrity of our parliamentary institutions."

READ: Conflict of Interest and Ethics Commissioner's letter to Pat Martin