Justin Trudeau's Liberals launched their full campaign platform on Sunday with promises of new support for post-secondary students and graduates, paid for, in part, by new taxes on internet giants and luxury goods.

In total, the Liberals are proposing new investments of $9.3 billion in 2020-2021, rising to $17 billion in the fourth year of a second mandate. The federal deficit would increase to $27.4 billion in 2020-2021, declining to $21 billion in 2023-2024.

The Liberals promised in 2015 to run three years of deficits before returning the federal budget to balance in 2019.

With the new promises, the federal debt-to-GDP ratio would still decline, from 30.9 per cent in 2020-2021 to 30.2 per cent in 2023-2024.

Politically, the Liberal platform increases the party's contrast with the Conservatives, between a Liberal proposal to spend more and a Conservative commitment to spend less. The Liberal proposals might also reduce the space between themselves and the NDP, their rivals on the left.

The Liberal party's platform adds $9.3 billion in new spending, but Liberal Leader Justin Trudeau says their financial track is sustainable as long as the economy continues to grow in relation to the federal debt. 2:14

"We are making a different choice than the Conservatives do. We're choosing to invest in middle-class Canadians, invest in people's communities, because, quite frankly, that is what has worked over the past four years," Trudeau told reporters at an event in Mississauga, Ont.

"Conservatives are still making the argument that the way to grow the economy is through cuts and austerity and tax breaks that go to the wealthiest. We disagree. Our plan is focused on investing in Canadians, in a fiscally responsible way that means the size of our debt in relation to the size of our economy is low and will keep getting lower every single year."

During his prepared remarks, the Liberal leader highlighted a series of cuts that are being made in Ontario under the Progressive Conservative government of Doug Ford.

At a news conference to respond to the Liberal platform, Conservative finance critic Pierre Poilievre scorned the new spending commitments.

Ontario Conservative Pierre Poilievre goes after the Liberal's plan to increase spending with no plan to balance the budget. 0:18

"This is Justin Trudeau's credit card campaign," Poilievre said, alleging that the Liberals were concealing future tax increases. "He expects Canadians to believe that money falls out of the sky or grows on trees."

The Conservatives have not yet released their full platform. They have previously promised to balance the budget by 2024.

In his own response, NDP leader Jagmeet Singh said his party would do still more to help students and those struggling with the cost of prescriptions and housing.

"What Mr. Trudeau and the Liberals are doing [is] they're trying to scare people into settling for less," Singh said. "You don't have to settle for less."

New help for students

Under the Liberal plan, the maximum annual amount available under the Canada Student Grant program would rise to $4,200, an increase of $1,200.

Interest charges on student loans would also not be charged for two years or until a graduate is making a salary of at least $35,000. In the event that an individual's salary drops below $35,000, interest charges would be suspended.

Finally, graduates who are new parents would have the option to suspend student-loan payments until their child reaches the age of five.

The NDP, Singh noted, is promising to eliminate interest on all student loans.

After the Liberals released their full platform, NDP Leader Jagmeet Singh was asked if he is worried they are trying to out flank the NDP on the left. 1:20

Tax on digital giants, luxury goods

To raise new revenue, the Liberals are proposing a 10 per cent "luxury tax" — an additional excise tax on luxury cars, boats and personal aircraft that sell for more than $100,000.

Digital companies that make at least $1 billion in annual global revenues and at least $40 million in Canadian revenues — firms like Amazon, Google, Netflix, Apple and Facebook — would pay a three per cent tax on revenue generated through sales of online advertising and user data.

The Liberals would also undertake a new review of federal spending and tax expenditures, with a focus on tax measures that "disproportionately benefit Canada's wealthiest individuals and large corporations."

The Liberal platform does not specify any items in particular to cut, but the Liberals hope to find $2 billion in savings in 2020-2021, rising to $3 billion in four years.

The office of the parliamentary budget officer warned that the platform's projections for the new revenue measures came with a high degree of "uncertainty," because of a number of variables. But the Institute of Fiscal Studies and Democracy, a think tank that is analyzing party platforms for transparency and reasonableness, gave the Liberal platform a passing grade.

New powers for privacy commissioner, terrorism prosecution

The 85-page Liberal platform restates a number of existing commitments and policies already implemented. But it does include a number of new promises.

The federal minimum wage, for instance, would rise to $15 per hour and the Liberals would create a $200 "culture pass" available to every child when they turn 12 to cover the cost of theatres, museums, art galleries and other cultural venues.

The federal child disability benefit would also be doubled.

The Liberals are promising to implement mandatory training for judges on sexual assault, effectively reviving a measure put forward in a private member's bill by former Conservative MP Rona Ambrose. Survivors of sexual assault and intimate partner violence would be provided with free legal aid.

The privacy commissioner would be empowered to enforce a new digital charter that gives internet users greater power over the use and retention of their data and social media platforms would be required to remove illegal content, including hate speech, within 24 hours.

In partnership with Indigenous leaders, a Liberal government would co-develop legislation to cover Indigenous health care, infrastructure in Indigenous communities and the implementation of the United Nations Declaration on the Rights of Indigenous Peoples.

The Liberals would also create a director of terrorism prosecutions, a new office with a mandate to pursue cases of Canadians who travel abroad to join terrorist organisations. Funding for the federal anti-racism strategy would also be doubled, to $90 million from $45 million.

Not addressed in the Liberal costing is a commitment to invest in pharmacare. Trudeau said that will be subject to negotiation with the provinces.

Previously announced items

Among the commitments already announced during the campaign, the Liberals have promised to: