EDMONTON -- The largest union in western Canada has launched a legal challenge against new provincial legislation put into law by the UCP government, saying it violates Canada’s constitution.

The Alberta Union of Provincial Employees (AUPE) says Premier Jason Kenney’s Bill 1 is in breach of individuals’ charter of rights and freedoms.

Bill 1, the Critical Infrastructure Defence Act, was passed into law last week.

The new law allows the government to levy heavy fines and possibly imprison anyone found to be unlawfully interfering with infrastructure like pipelines, highways, utilities and oil and gas production facilities.

In a statement of claim filed at the Court of Queen’s Bench of Alberta Tuesday, the union said the law will “substantially hinder AUPE’s ability to meaningfully engage in the collective bargaining process.”

AUPE president, Guy Smith told CTV News Edmonton that the expansiveness and vagueness of the law means it could be used to prevent workers from standing up for their rights.

“Anytime that we hold a protest or demonstration or an information picket or a leafleting campaign on a sidewalk, we could potentially be breaking the law,” said Smith.

Bill 1 was introduced after a series of protests blocked railway lines across the country, in support of the Wetʼsuwetʼen hereditary chiefs in British Columbia and their opposition to the Coastal GasLink Pipeline project.

“I know that the focus has been on the railway blockades and the pipeline protests and that sort of thing,” Smith said. “But it really is more expansive than that and that's what we're concerned about.”

In a news release sent out Tuesday, the AUPE called Bill 1: “The kind of law we would expect to see in an oppressive dictatorship.”

“It’s obvious the government’s intent is to crush opposition against their unpopular policies and reckless cuts to services,” Smith said.

The AUPE, which represents 95,000 public service workers, says it’s willing to take its case to the Supreme Court.