• by Wendy Davis , Staff Writer @wendyndavis, January 8, 2015

The Federal Trade Commission hauled AT&T into court last October for throttling the mobile broadband speeds of wireless customers who pay for unlimited data.

This week, the telecom fired back by asking for the lawsuit to be dismissed on the grounds that it's a “common carrier” and, therefore, not subject to FTC jurisdiction. “The FTC lacks authority to bring suit against AT&T,” the company argues in papers filed with the U.S. District Court for the Northern District of California.

The company adds that its entitled to dismissal even though mobile data isn't subject to common-carrier rules. “The fact that AT&T's mobile data services are not regulated as common-carrier services under the Communications Act is irrelevant,” the telecom writes. AT&T also says in its papers that it started throttling users in order “to preserve a high quality experience for all of its customers, by preventing heavy users of data from overwhelming the mobile network and degrading service for all.”

If that's AT&T's goal, however, the throttling plan seems an odd way for the company to achieve its aims -- especially given that the company slows down users regardless of whether the network is congested.

The FTC specifically alleged in its complaint that AT&T slows down unlimited subscribers after they hit specific data caps -- 3 GB a month for customers on 3G and HSPA+ networks, and 5 GB a month for people on LTE -- even when the network is running smoothly.

AT&T also argues that the lawsuit should be dismissed because the company is already subject to jurisdiction of a different agency -- the Federal Communications Commission. “Whether AT&T’s network management program is 'unfair' and whether its disclosures were 'inadequate' are issues for the FCC to decide, and in fact the FCC is in the process of so deciding,” the company writes.

Of course, even if the court agrees with AT&T and dismisses the lawsuit, the FCC could well decide that the company shouldn't be throttling subscribers on unlimited plans.

Chairman Tom Wheeler has already indicated that he disapproves of the practice. Earlier this year, he convinced Verizon Wireless to back away from a controversial plan to throttle some of its longtime subscribers who are still on unlimited data plans.

Verizon had said in July that some of its unlimited users might be slowed down when using high bandwidth applications, like streaming video or playing online games.

Wheeler quickly criticized the plan. “I know of no past Commission statement that would treat as 'reasonable network management' a decision to slow traffic to a user who has paid, after all, for 'unlimited' service,” he wrote to Verizon in July.