The Liberal government has advised its cabinet to oppose a private member's bill intended to increase the number of women running for Parliament, according to a document obtained by CTV News.

Bill C-237, proposed by New Democrat MP Kennedy Stewart, would penalize federal political parties that don't come close to running gender equitable slates of candidates. The Liberals haven't committed to supporting the bill, but have suggested as recently as this week that they are open to it.

"We take note of [Stewart's] private member's bill and will study it on its merits when it is debated in the House," Democratic Reform Minister Maryam Monsef said Tuesday in question period. "Our government supports the idea of more women and people of various genders participating in the political debate in the country."

But the document, labelled a private member's business bill kit and dated May 6, seems to contradict that. Under "government position/recommendation," it notes: "Oppose." 

The briefing was distributed to cabinet, according to the source who provided it to CTV News. It outlines a number of reasons to vote against the bill, which would withhold a percentage of a party's campaign spending refund if it doesn't hit the target of having women run for 45 per cent of seats.

A spokesman for Prime Minister Justin Trudeau said he couldn't comment on cabinet discussions, whether to confirm or deny the document's authenticity. Mark Holland, Monsef's parliamentary secretary, said he doesn't see it as a direction to cabinet.

"I see it as a backgrounder for people to take a look at what the information is and what the concerns are," Holland told CTV News.

Several of the problems raised in the briefing note seem to be easy to fix through amendments to the proposed law. Stewart also disputes some of the points based on advice he says he's gotten from the House law clerk.

The Liberal briefing note says the bill doesn't account for transgender candidates, although Stewart says the 45 per cent target allows for some flexibility. The document also says Stewart's bill doesn't account for smaller parties that run few candidates - for example, it posits a single-candidate party would lose 22.5 per cent of its refund just because it only had one person running. But that may not be a concern since parties must get at least two per cent of the vote across the country, or five per cent in each riding in which they run candidates, to be eligible for the refund.

The document also raises concerns about refusing the nomination of qualified candidates based on their gender, arguing the bill limits the independence of parties.

"We have underrepresentation of a number of different minorities in the House... I think there's a fair question to say if we do this for women, why aren't we doing it in other examples? Why aren't we setting other thresholds and why aren't we using the same mechanisms?" Holland said.

Stewart's bill forces a party leader to interfere in local riding contests and appoint a candidate, Holland added.

Stewart says he’s open to changing the bill, whether that means lowering the target for female candidates or providing financial incentives rather than penalties. But private member’s bills can’t legislate spending, so the government would have to authorize the bill to do so.

"All we need to do is get this to the standing committee, and then I’m prepared to make any changes that they want to make," he said.

The bill has one more hour of debate, likely next fall, before MPs will vote on it. That vote can kill it entirely or move it to committee stage.

Several Liberal MPs support the bill, Stewart said in a news release Tuesday, noting Pam Damoff, vice-chair of the status of women committee, Toronto MP Nathaniel Erskine-Smith, and Halifax MP Andy Fillmore have endorsed C-237.