Two wireless carriers in Canada have been ordered to stop exempting their mobile TV services from data caps in a ruling that targets discrimination against competing online video services.

The Canadian Radio-television and Telecommunications Commission (CRTC) issued the ruling today against wireless carriers Bell Mobility and Videotron, which each offered mobile TV services and exempted them from data caps. The country's telecommunications law "prohibits Canadian carriers from conferring an undue disadvantage to others, or an undue preference to itself or others," the commission said. "Bell Mobility and Videotron have given an undue preference in favour of subscribers of their respective mobile TV services, as well as in favour of their own services, and have subjected consumers of other audiovisual content services, and other services, to a corresponding undue disadvantage."

The commission directed Bell "to eliminate its unlawful practice with respect to data charges for its mobile TV service" by April 29, 2015. Videotron must confirm by March 31 that it has completed the withdrawal of its TV app from BlackBerry and Android phones, "thereby removing any undue preference for its mobile TV service, and ensure that any new mobile TV service complies with the determinations set out in this decision."

Bell and Videotron each charged subscribers monthly and hourly fees to view video on their mobile devices, but customers could watch as much as they wanted without getting charged for more data. Videotron is a cable company but also offers wireless service outside of its cable territory.

"The case arose from a complaint filed by Ben Klass, a graduate student, who noted that Bell offers a $5 per month mobile TV service that allows users to watch dozens of Bell-owned or licensed television channels for ten hours without affecting their data cap," University of Ottawa law professor Michael Geist wrote today. "By comparison, users accessing the same online video through a third-party service such as Netflix would be on the hook for a far more expensive data plan since all of the data usage would count against their monthly cap. Videotron was later added to the case, based on similar concerns with its mobile television service."

Bell argued that it was subject to broadcast regulation instead of telecom regulation, but the CRTC "ruled that mobile television services effectively invoke both broadcast and telecom regulation, since a data connection is required to access the service," Geist wrote.

In the US, AT&T has been charging online content providers for the right to exempt their services from data caps. (AT&T also argued in 2012 that it could limit the use of Apple's FaceTime to certain types of data plans.) T-Mobile exempts music services it offers with partners from data caps, but it also exempts music services from competitors. FCC Chairman Tom Wheeler has fought wireless carriers over their throttling of unlimited data plans, but the status of net neutrality rules for wireless is unsettled.

Wheeler's first net neutrality proposal last year exempted wireless carriers from some of the anti-discrimination rules applied to fixed Internet providers, but he is scheduled to unveil a new net neutrality plan next week that could put wireless and fixed on more equal footing.