Wednesday was an eventful day for the House of Commons. Perhaps even an important one, precisely because it was so eventful.

In the climactic moment, 105 Liberals broke with the government and voted in favour of S-201, a bill sponsored by Liberal MP Rob Oliphant to ban genetic discrimination.

Moments earlier, 27 Liberal backbenchers had provided the decisive votes in favour of S-217, Conservative MP Michael Cooper's bill on detention in custody — again, against the position of the Liberal government.

Less noticed, but still noteworthy, was the cabinet's own move a few hours earlier to amend C-22, a government bill that would establish a committee of parliamentarians to review national security operations.

Liberal members of the public safety committee joined with Conservatives and New Democrats to amend the bill late last year. On Wednesday afternoon, the government brought forward its own amendments to counter some of the committee's changes.

The prime minister has, rightly or wrongly, punted on electoral reform. Parliamentary procedures remain basically unchanged, though the government has at least now released a discussion paper and the Senate continues to be a live experiment in legislative independence.

The access to information system is still awaiting reform. Question period is still a mostly drab exchange of accusations and platitudes.

But interesting things keep happening nonetheless; indications that the House of Commons might be slowly changing.

Liberal MPs go their own way

With a few exceptions, the last Parliament wasn't generally given to such dramatic demonstrations of independent thought. But Wednesday was actually not the first time during this Parliament that Liberal backbenchers have decisively swung a vote.

Liberal backbenchers helped swing two votes against the wishes of Prime Minister Justin Trudeau and his cabinet on Wednesday. (Chris Bolin/Reuters)

On Oct. 26, 103 Liberal MPs voted to support Bill C-243, Liberal MP Mark Gerretsen's bill on maternity benefits. And, that same day, 90 Liberals voted in favour of Bill C-240, Liberal MP Bryan May's bill to create a tax credit for first-aid training.

In both cases, Liberal cabinet ministers voted against.

But C-243 and C-240, along with S-217, were at the second-reading stage of the process and Liberals were merely voting to send the bills to committee for further study.

With S-201, the ban on genetic discrimination, Liberal backbenchers were voting to pass the bill into law.

Siding with committee over prime minister

According to Liberal sources, both the prime minister and Justice Minister Jody Wilson-Raybould addressed caucus Wednesday morning about why the government opposes S-201. As Justin Trudeau explained to reporters that day, the cabinet believes the bill violates provincial jurisdiction.

But nearly the entire Liberal backbench and a dozen parliamentary secretaries disagreed, siding with the House committee that studied the bill.

"I felt that the House justice committee came to the correct result in its deliberation and remain convinced that the important human rights concerns outweigh the concern that the bill might be ultra vires," explained Nick Whalen, the Liberal MP for St. John's East.

Did it feel odd to vote in favour of a bill that the prime minister spoke out against?

"Our obligation to use free votes for the best interest of the country and our constituents was a campaign commitment, and needs to overcome my natural desire to vote with the government," Whalen said. "So, yes. It feels odd, but it is part of a healthy working relationship and what should happen from time to time."

Liberal backbenchers defy cabinet wishes, vote to enact genetic discrimination law 6:48

Immediately after the vote, Oliphant was enthused.

"I think the new reality is that Liberal backbenchers are being empowered," he told reporters. "And I think that we're really trying to see how Parliament can change."

The life of a backbench MP

Excessive party discipline and the limited relevance of the backbench MP are the eternal laments of the Westminster parliamentary system.

But the last Parliament ended amid particularly loud complaint about the state of things — personified by Brent Rathgeber after he quit the Conservative caucus to sit as an independent — and the Liberals came to office with some suggestion things would be somehow different.

Nathaniel Erskine-Smith, the Liberal MP for Beaches-East York in Toronto, is developing a reputation for voting his own way in the House of Commons. (Nathaniel Erskine-Smith)

And things have at least been somewhat different. There were hints of a livelier Parliament last spring and one Liberal MP, Nathaniel Erskine-Smith, has now managed to break from the party line on 13 per cent of his votes — far more than recent precedent and roughly in line with the most independent-minded members of the looser British Parliament.

Oliphant theorizes that Liberal MPs, having campaigned on a promise of more independence for MPs and House committees, are now getting comfortable in their new jobs. And the prime minister, having promised to only whip votes in specific circumstances, isn't whipping every vote.

With S-201, Oliphant says the result wasn't a division within caucus, but a mere difference of opinion. He suggests Conservatives and New Democrats are still getting used to the new reality, too.

"I think we're in a transition time," Oliphant said Thursday, reflecting on S-201's victory.

Delivering change?

Though MPs from the governing party often function as extensions of the government, they are also simply MPs, sitting outside cabinet and with some responsibility to hold the government to account. That was one of the messages Rathgeber tried to convey as he took on the cause of reform.

Brent Rathgeber speaks about his decision to quit the federal Conservative caucus in St. Albert, Alta., in 2013. (Jason Franson/Canadian Press)

And while self-interest often holds partisans of the same stripe together — politics is still a team sport — a system that allows for greater independence could have some benefits. Legislation and spending might be better scrutinized. Public concerns and potential problems might be better aired. MPs who never ascend to cabinet might be able to establish themselves as important legislators.

Or so the reform-minded might dream.

It remains to be seen whether the spirit of Wednesday will continue on or evolve.

Liberals can say this is the change they promised. Wednesday's votes, and the upset that night in a Liberal nomination race in St. Laurent, might suggest a party whose members are not easily controlled anyway.

With the example of S-201, the prime minister might learn to get behind his caucus when its opinion seems to be moving against him. Or his willingness to tolerate dissent might be tested.

But regardless of whatever rules or procedures are rewritten, the potential for change would likely still depend on how MPs assert themselves. And at the very least, Wednesday might suggest that some change is possible.