Mozilla's logo at the 2014 Mobile World Congress. (Mozilla)

It's not often you see a top net neutrality advocate picking apart arguments from her own side. But anticipating critiques and addressing them is an important part of any debate, and the exercise appears to have uncovered some flaws in a proposal put forward by Mozilla, one of the open Internet's biggest champions.

Mozilla's proposal to federal regulators, in a nutshell, involves highlighting the relationship between Internet service providers (ISPs) and content companies like Amazon, YouTube and Xbox Live, and regulating that relationship more heavily than the relationship ISPs have with consumers. It's a more limited move than what some net neutrality advocates have proposed, which is to impose stiffer regulations on ISPs more generally.

Stanford University law scholar Barbara van Schewick is among those who've pressed for such regulations. A leading proponent of tougher net neutrality rules, van Schewick has argued that the Federal Communications Commission could use a part of its charter — Title II of the Communications Act — to prevent ISPs from charging content companies for faster, better access to consumers. Consumer groups say that if ISPs are allowed to engage in this "paid prioritization," it would create an unfair playing field on the Internet and could strangle startups and small businesses that can't afford to pay.

But in a meeting with the FCC this month, van Schewick pointed out three tiny words that threaten to undermine Mozilla's proposal to regulate ISPs — or a part of what they do, anyway — as telecommunications services.

"The definition of 'telecommunications service' requires that telecommunications is offered 'for a fee,'" van Schewick wrote in a report on her meeting.

That's problematic, van Schewick argued, for a couple of reasons. If the FCC adopts Mozilla's proposal, then the FCC's net neutrality regulations wouldn't cover Internet providers that don't charge content companies an access fee. This might sound like a good thing for consumers, except that it wouldn't prevent other forms of content discrimination, leaving open the possibility that ISPs find a way to get around the fee-based rule. (From a different perspective, though, it's possible that unpaid prioritization would help differentiate one ISP from another, theoretically improving competition in areas that are served by more than a couple providers.)

More troubling to van Schewick, though, is how the phrase "for a fee" would complicate efforts to ban fee-based content prioritization. At a basic level, what Mozilla is asking the FCC to do is to single out fee-charging ISPs (because non-fee-charging ISPs would be exempted under the definition of "telecommunications service") and then turn around and tell them, based on that very same part of the Communications Act, that they can't charge those fees. Van Schewick didn't immediately respond to a request for an interview.

It's not hard to envision someone challenging that move on the grounds that it amounts to arbitrary and capricious regulation, van Schewick told the FCC. Mozilla responded by pointing to a recent FCC filing which it argued that Title II doesn't say who should be paying the fee. The fact that ISPs universally charge consumers for Internet access is enough for the FCC to apply Title II regulations to attempts at traffic discrimination by all ISPs, whether they charge content companies a fee or not. (See the bottom of page 11 of Mozilla's filing, linked above, for the relevant section.)

How convincing is that argument? A legalistic reading of "for a fee" might give Mozilla the benefit of the doubt. But think about what Mozilla is asking the FCC to do: Ignore the relationship between consumers and ISPs for the purpose of applying Title II to the relationship between content companies and ISPs, but then justify that policy based on the very relationship between consumers and ISPs that Mozilla wants the FCC to set aside.

Part of what makes van Schewick's meeting so interesting is her advocacy of Title II as a hedge against ISP overreach. Her critique of Mozilla's plan also adds to other potential gaps in the Title II argument, such as that Title II wouldn't prevent attempts by ISPs to prioritize content by claiming the practice represents just and reasonable attempts at network management. Some reclassification proponents I've spoken to admit they don't have a very compelling rejoinder to that argument.

There's a lot to unpack in this exchange. But it wouldn't be an honest debate without some self-criticism, which appears to be what's going on here.