Federal Liberals have traditionally been more malleable and more politically nimble than their Conservative and NDP opponents.

It's often said that Liberals will campaign from the left and then steer to the right after elections.

They'll shift and shimmy, depending on the political circumstances.

On the one hand, former leader Pierre Trudeau said the state has no place in the bedrooms of the nation, making him appear like a great civil libertarian.

Then he released a white paper proposing the full assimilation of Indigenous people. A year later, he dispatched the army into the streets of Montreal and allowed police to round up hundreds of people following two kidnappings.

Then, in another twist, Pierre Trudeau introduced the Canadian Charter of Rights, radically transforming the rights of individuals vis-a-vis the state. That ushered in new liberties, preserving his reputation in history. But he had to be pushed like hell by First Nations leaders and the NDP to recognize and affirm Aboriginal and treaty rights in the constitution.

The same pattern occurred through the years of Jean Chrétien's rule. He campaigned against the GST but embraced it after the election. He eliminated national standards for social assistance, but then kept Canada out of the U.S.-led war against Iraq.

Liberals tend to be far less xenophobic than Conservatives, which is a major reason for their political successes since the Second World War.

It's a similar story with Justin Trudeau, who also can't be accused of being xenophobic. He cancelled the Enbridge pipeline to the West Coast but has been gung-ho to proceed with three other pipelines.

He talks a good game on the climate, but retained the Harper government's greenhouse-gas emission targets and is failing to meet them.

Justin Trudeau claims to place the government's relationship with Indigenous peoples above all others. Yet he continued granting federal permits for the Site C dam while it was before the courts, benefiting engineering companies like SNC-Lavalin, and he mocked a protester worried about mercury contamination on a reserve.

Justin Trudeau purports to hold the justice portfolio in high regard. Yet he's the first prime minister who's been exposed as trying to derail a criminal prosecution.

His eagerness to do this appears to be the reason he fired his justice minister and attorney general, Jody Wilson-Raybould, notwithstanding denials by him and his close friend Gerald Butts.

Even though the federal Liberals are closer, ideologically speaking, to most voters (as opposed to those who don't vote) than their chief competitors, they always seem to get derailed over issues of principle and ethics.

To many Canadians, it was unethical for Justin Trudeau to try to interfere in a criminal prosecution. End of story.

Canadians feel this way even without fully understanding the niceties of the constitutional concept of prosecutorial independence.

In a nutshell, it states that prosecutors, just like police and the judiciary, should act independently to protect against elected officials meddling in areas where they're not supposed to tread. The rule of law is supposed to inoculate the country from politicians deciding who should be prosecuted.

Because Liberals tend to be more slippery than many of their counterparts in the NDP and the Conservatives, they don't, for the most part, have a big problem with their prime minister crossing this line.

All you have to do is listen to the comments of people like Transport Minister Marc Garneau, Toronto-area MP Judy Sgro, or Fisheries Minister Jonathan Wilkinson. Witness the ovations the prime minister received from veteran members of his caucus yesterday.

In the same manner, federal Liberals weren't too bothered by the elimination of national standards for social assistance in 1995. This had been a hallmark of our social-welfare system since the days of Lester B. Pearson.

It didn't bug them, even though this led to a race to the bottom among provinces when it came to providing social assistance. That, in turn, set the stage for the current homelessness crisis gripping the nation.

Now, federal Liberals could be on the verge of breaking the dam of prosecutorial independence. And they're using the fig leaf of a taped phone conversation, which Justin Trudeau called "unconscionable", as their justification to banish two whistle-blowers who felt that this was wrong.

While the meddling in the SNC-Lavalin criminal prosecution may persuade Canadians to throw the federal Liberals out of power, this action must be seen for what it is—yet another symptom of the rot within the federal Liberals.

It's a party that too often seems to lack a moral or ideological compass. That's why it's had a tendency to attract those who will shift their positions, often quite eagerly, depending on the circumstances. They're Liberals of convenience.

So even if Justin Trudeau is pushed out, he'll likely only be replaced by another politician who will behave in a similar manner.

That's the Liberal way.