The final sitting of Parliament before a federal election is a time when parties test their messages and refine the arguments they will take on the campaign trail.
On Tuesday, Conservatives put forward an opposition motion calling on the prime minister to produce a plan to eliminate the deficit and to pledge in writing that "he will never raise taxes of any kind." Though the motion was easily defeated, the Tories are now boasting that the Liberals won't rule out tax hikes if they win again in October.
The fall election also loomed large in question period, the 45 minutes MPs spend together each day in an attempt to hold the government to account.
This week, we saw opposition MPs use carefully crafted lines of attack against the government — and counterattacks from the Liberals — that provide some clues on how the federal campaign may shape up.
Here are a few things that stood out.
Conservatives kept referencing Trudeau's 'family fortune'
It's not a new strategy for rival MPs to point out that Prime Minister Justin Trudeau comes from a privileged background. Back in January of 2015 — another election year — then-prime minister Stephen Harper took a thinly-veiled jab at Trudeau's inheritance during question period when he said most Canadians can't rely "on a personal trust fund."
Conservatives were beating that drum repeatedly in the House this week while arguing that Trudeau does not know how to control government spending.
"It is not surprising the prime minister does not worry about Canadians' money," Tory Leader Andrew Scheer said Monday. "He has never had to worry about money. He has never had to balance a household budget."
"The prime minister will not have to worry about paying his carbon tax on the necessities of life because the millions in his trust fund will look after his family just fine," offered Tory finance critic Pierre Poilievre.
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The newest Tory MP, Michael Barrett, who in December won a byelection in the Ontario riding Leeds—Grenville—Thousand Islands and Rideau Lakes, used his first question in the House to bring up the PM's personal finances. While bashing the Liberals' carbon pricing plan, Barrett noted that "farmers in my riding did not inherit a family fortune like the prime minister."
Trudeau shot back by accusing the Tories of stooping to "snide personal remarks."
When he ran for the Liberal leadership, Trudeau voluntarily disclosed details about his personal wealth, including a $1.2 million inheritance from his father, former prime minister Pierre Trudeau.
Liberals kept noting Scheer promised a climate plan hundreds of days ago
Trudeau has already suggested he's willing to fight the next election on his government's carbon pricing plan, saying his Tory rivals want to make pollution free again.
In April, his government will impose a price on carbon emissions of $20 per tonne in four provinces that have refused to develop their own plans: Ontario, Saskatchewan, Manitoba, and New Brunswick. That price will rise by $10 a year until it hits $50 per tonne in 2022.
The government is promising to return the money it collects in the form of rebates. They say the average household refunds will be $256 in New Brunswick, $300 in Ontario, $336 in Manitoba and $598 in Saskatchewan.
While Scheer's Conservatives say carbon pricing will mean doom and gloom, they have not revealed how they might tackle climate change.
In question period this week, Trudeau and Environment Minister Catherine McKenna took some pleasure in noting how many days have gone by since Scheer said a Conservative climate plan was on its way.
"When it comes to climate change, it has been 274 days since the member opposite promised a climate plan for Canadians. Where is that plan?" Trudeau asked Monday.
On Wednesday, Trudeau noted Scheer "promised to deliver a plan to fight climate change 276 days ago and we are still waiting."
On Thursday, Sean Fraser, parliamentary secretary to the environment minister, mentioned that 277 days had gone by without a Tory climate strategy.
You get the idea.
NDP kept pushing housing, housing, housing
The New Democrats largely kept their focus on housing shortages in Canada, a situation that they say has become a crisis. Their MPs repeatedly pressed Trudeau and Social Development Minister Jean-Yves Duclos on the issue this week.
Both responded that the government had spent $5.7 billion on affordable housing since 2016 and they touted the national housing strategy, unveiled in November 2017. Though the Liberals promised to spend $40 billion over the next 10 years, NDP MPs have noted that much of the money won't be spent until after the next election.
"More than 1.5 million Canadian households are in urgent need today. New investments are needed right now, not in three or four years," the NDP's parliamentary leader Guy Caron said.
The prime minister ran into some trouble when he claimed the plan had "already helped more than one million Canadians find housing," a figure that Liberal MP Adam Vaughan later told The Toronto Star was torqued "to rhetorical advantage."
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The NDP pressed for funding to address the issue in the next federal budget, expected in February or March.
So, what could this laser focus on housing have to do with the next federal election?
NDP Leader Jagmeet Singh is currently fighting a byelection in the B.C. riding of Burnaby South, where housing is a major issue. If he loses the byelection, the NDP could be looking for a new leader at a time when the other parties are gearing up for a national campaign.
Last month, Singh said an NDP government would build 500,000 affordable housing units across the country over the next decade.
Tories kept claiming the carbon tax will go up to $300 per tonne
"We now know that if allowed to continue, the government will raise the carbon tax drastically after the next election," Scheer said this week. "Based on the government's own figures, the carbon tax could rise as high as $300 per tonne."
"Government documents show the carbon tax will be 15 times higher if the Liberals are re-elected. That's up to $5,000 per year for a family of four," Tory MP John Brassard added.
The Tories were referencing a memo Environment Canada sent to McKenna in 2015 — later obtained by the National Post — that suggested a carbon price would need to go that high by 2050 for Canada to meet its climate targets.
The Liberal carbon pricing has no details beyond 2022.
Sean Fraser, McKenna's parliamentary secretary, accused Tories of resorting to "desperate" scare tactics.
"We have never indicated once that we plan to move forward with a figure anywhere close to the one (Conservatives are) talking about," he said.
McKenna, meanwhile, argued in question period that Canadian families are already paying the price of climate change.
"Does the party opposite understand that climate inaction is a huge cost and that the Conservatives are passing that cost to their kids, that climate change is real and that Canadians deserve a plan?" she asked.
And Trudeau reminded everyone of Scheer's Brexit support
It wasn't surprising that Trudeau faced many questions about his government's handling of relations with China and his decision to fire ambassador John McCallum.
Scheer called Trudeau's foreign policy a "disaster" and suggested it was part of a pattern. Twice, he accused the prime minister of "clowning around in India" during his much-maligned trip last year.
But Trudeau fired back saying he would "take no lessons" from a leader "whose only pronouncement on foreign policy has been to come down on one side of the most divisive, destructive debate to happen in the U.K. for an awfully long time."
Scheer wrote an op-ed for the National Post in June 2016 outlining why he thought it was a good idea for Britain to leave the European Union. In contrast, Trudeau made it clear he wanted Britain to remain in the EU.
During the 2017 Tory leadership race, Scheer also tweeted that he was "pro-Brexit before it was cool."
In November, the Conservative leader told The Canadian Press that he still supports Britain leaving the EU, even though the issue has sparked chaos across the pond.
But rather than let Trudeau's Brexit jab slide, Scheer doubled down.
"The prime minister came down on the losing side of that debate in the United Kingdom," Scheer said, before moving back to relations on China.
In a possible sign of things to come, Trudeau pivoted back to Brexit.
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"Mr. Speaker, the member opposite just did it again," Trudeau said. "He came down clearly on one side of the most divisive foreign policy debate to hit the United Kingdom in a long time. He even boasted about it, saying that he was pro-Brexit before Brexit was cool.
"Quite frankly, we will take no lessons from the members opposite on the matter of Canada's standing in the world and the great work we are doing on foreign policy."
Canadians are scheduled to head to the polls on Oct. 21.
With files from The Canadian Press
Earlier: Trudeau, Scheer look ahead to 2019 election