Doug Ford can likely invoke parliamentary privilege to avoid the Emergencies Act inquiry. Should he?

Doug Ford may be on solid legal footing as he seeks to invoke parliamentary privilege and avoid testifying at the Emergencies Act commission — but some experts question whether the Ontario premier is abusing the tactic.

"He's using it in such a powerful way that it's basically using parliamentary privilege almost as a sword," said Mary Liston, an associate professor at the University of British Columbia's Peter A. Allard School of Law.

"Like you're protecting yourself — but you're being aggressive about it."

Ford and his former solicitor general Sylvia Jones were on Monday summoned to testify before the Public Order Emergency Commission, which is investigating the governmental response to last winter's truck convoy protests. 

The next day, lawyers for Ford and Jones filed an application for judicial review in Federal Court seeking to quash the summons, citing parliamentary privilege. They argue that the summons breaches that privilege by attempting to compel Ford and Jones to testify.

The move, said Liston, creates tension between the separation of powers and "other important constitutional principles, like the rule of law, like responsible governments, our whole democratic tradition of accountability and holding government to account."

It is a "kind of a potential, mini-constitutional crisis."

Ford's court filing argues that parliamentary privilege protects members of the Ontario Legislative Assembly from being compelled to testify in any proceeding while the legislature is in session, and, in practice, for 40 days before and after each session and periods when the house is adjourned.

"The summonses were issued without jurisdiction, pursuant to an error of law, and must be quashed," the application said. "Irreparable harm will occur if a stay is not granted."

Liston says Ford and Jones must prove that testimonial immunity — which is an important aspect of parliamentary privlege — applies in this case. 

"And I think they'll be able to do that quite easily," she said. "But then you get into these grey areas of, well, what's the scope of that?"

Steven Chaplin, a lawyer who has advised the federal government on constitutional law questions, including parliamentary privilege, says Ford's legal team has good legal and constitutional grounds to claim the privilege.

"Now, whether or not it's the proper use or not, that's another thing," he said.

Chaplin said the issue of parliamentary privilege has previously been taken up in the courts. The Supreme Court of Canada in a 2005 case, for example, set out several privileges to which provincial legislatures have a right — including immunity from being summoned in civil matters.