The Canadian province of Quebec’s controversial plan to IP-block online gambling sites is facing its first official challenge.

On Monday, the Public Interest Advocacy Centre (PIAC) filed an application (read it here) with the Canadian Radio-Television and Telecommunications Commission (CRTC), asking it to reject Quebec’s Bill 74 as an unconstitutional challenge to federal control over the internet.

In May, the Quebec legislature approved Bill 74, omnibus legislation that contained language compelling the province’s internet service providers to block the domains of online gambling sites not run by the Loto-Quebec gaming monopoly or any privately operated sites that Loto-Quebec chooses to license (such as Montreal-based Amaya Gaming’s PokerStars brand).

Civil libertarians have decried Bill 74 as an unprecedented act of online censorship while recent court rulings have affirmed the precept that telecommunications fall under federal jurisdiction, making Quebec’s nakedly profit-based protectionism liable to a constitutional challenge.