Adam Schwartz, staff attorney with the digital rights group Electronic Frontier Foundation, said that he sees Proposition 24 as "a mixed bag of partial steps backwards and partial steps forwards, and a lot of missed opportunities."
"One of our north stars is a private right of action," Schwartz said. "If you don't have effective enforcement, then you just have a piece of paper, and no matter what agency you put in charge of enforcement it's not going to have enough resources to bring an action against every company that violates the law."
Schwartz also believes that opt-in should be the norm, given that most people don't have the time or expertise to figure out how to adjust the settings on every service they use to maximize their privacy.
"What we really need is a new paradigm," Schwartz said. "We are better off having the right to opt out of the sale, plus a government agency to enforce it, than we were before, but it is not adequate to the task."
EFF, which has often led the charge for new privacy regulation in California, decided to neither support nor oppose the measure as a result.
Mactaggart has answers to these critiques.
"I had private right of action in the first draft" of the original ballot measure, Mactaggart said, but he feels obliged to stick to the terms of his compromise with Sacramento. "Whether I'm misguided or naive or whatever, I figure we had a deal," Mactaggart said. "I know this is a new initiative, but it felt like the basic premises were that I had sort of given my word."
He noted that Proposition 24 would allow district and city attorneys to bring actions against companies that violate the law, along with the new agency.
Mactaggart's rebuttal to the opt-in critique is more complicated. He's concerned that opt-in might face constitutional challenges, citing a 2011 Supreme Court ruling that found a Vermont opt-in requirement violated companies' 1st Amendment rights.
And he just thinks the opt-out system will work better in the long run. The goal, Mactaggart said, is to create a world in which everyone can just set their digital lives to "do not sell" and opt out of the entire system at a click, rather than picking and choosing where and when to opt in. To that effect, the text of Proposition 24 requires the state to create a universal "do not sell" signal that coders can build into browsers, phones or independent apps, and that every business subject to the law would need to respect.