Today’s paper is very similar to What Deters Jane from Preventing Identification and Tracking on the Web? and shares an author. The main difference is that it’s about email rather than the Web. The research question is the same: why don’t people use existing tools for enhancing the security and privacy of their online communications? (In this case, specifically tools for end-to-end encryption of email.) The answers are also closely related. As before, many people think no one would bother snooping on them because they aren’t important people. They may understand that their webmail provider reads their email in order to select ads to display next to it, but find this acceptable, and believe that the provider can be trusted not to do anything else with its knowledge. They may believe that the only people in a position to read their email are nation-state espionage agencies, and that trying to stop them is futile. All of these are broadly consistent with the results for the Web.

A key difference, though, is that users’ reported understanding of email-related security risks is often about a different category of threat that end-to-end encryption doesn’t help with: spam, viruses, and phishing. In fact, it may hurt: one of Gmail’s (former) engineers went on record with a detailed argument for why their ability to read all their users’ mail was essential to their ability to filter spam. [1] I’m not sure that isn’t just a case of not being able to see out of their local optimum, but it certainly does make the job simpler. Regardless, it seems to me that spam, viruses, and phishing are a much more visible and direct threat to the average email user’s personal security than any sort of surveillance. Choosing to use a service that’s very good at filtering, even at some cost in privacy, therefore strikes me as a savvy choice rather than an ignorant one. Put another way, I think a provider of end-to-end encrypted email needs to demonstrate that it can filter junk just as effectively if it wants to attract users away from existing services.

(In the current world, encryption is a signal of not being spam, but in a world where most messages were encrypted, spammers would start using encryption, and so would your PHB who keeps sending you virus-infected spreadsheets that you have to look at for your job.)

Another key difference is, you can unilaterally start using Tor, anti-tracking browser extensions, and so on, but you can’t unilaterally start encrypting your email. You can only send encrypted email to people who can receive encrypted email. Right now, that means there is a strong network effect against the use of encrypted email. There’s not a single word about this in the paper, and I find that a serious omission. It does specifically say that they avoided asking people about their experiences (if any) with PGP and similar software because they didn’t want to steer their thinking that way, but I think that was a mistake. It means they can’t distinguish what people think about email privacy in general, from what they think about end-to-end encryption tools that they may have tried, or at least heard of. There may be a substantial population of people who only looked into PGP just enough to discover that it’s only useful if the recipient also uses it, and don’t think of it anymore unless specifically prompted about it.

If you do a survey, large majorities of average people will say they don’t like the idea of other people snooping on what they do online. [1] [2] Yet, the existing bolt-on software that can prevent such snooping (at least somewhat) doesn’t get used by nearly as many people. The default explanation for this is that it’s because the software is hard to install and use correctly. [3] [4]

This paper presents a complementary answer: maybe people don’t realize just how ubiquitous or invasive online snooping is, so the benefit seems not worth the hassle. The authors interviewed a small group about their beliefs concerning identification and tracking. (They admit that the study group skews young and technical, and plan to broaden the study in the future.) Highlights include: People are primarily concerned about data they explicitly provide to some service—social network posts, bank account data, buying habits—and may not even be aware that ad networks and the like can build up comprehensive profiles of online activity even if all they do is browse. They often have heard a bunch of fragmentary information about cookies and supercookies and IP addresses and so on, and don’t know how this all fits together or which bits of it to worry about. Some people thought that tracking was only possible for services with which they have an account, while they are logged in (so they log out as soon as they’re done with the service). There is also general confusion about which security threats qualify as identification and tracking—to be fair, just about all of them can include some identification or tracking component. The consequences of being tracked online are unclear, leading people to underestimate the potential harm. And finally, many of the respondents assume they are not important people and therefore no one would bother tracking them. All of these observations are consistent with earlier studies in the same vein, e.g. Rick Wash’s Folk Models of Home Computer Security.

The authors argue that this means maybe the usability problems of the bolt-on privacy software are overstated, and user education about online security threats (and the mechanism of the Internet in general) should have higher priority. I think this goes too far. It seems more likely to me that because people underestimate the risk and don’t particularly understand how the privacy software would help, they are not motivated to overcome the usability problems. I am also skeptical of the effectiveness of user education. The mythical average users may well feel, and understandably so, that they should not need to know exactly what a cookie is, or exactly what data gets sent back and forth between their computers and the cloud, or the internal structure of that cloud. Why is it that the device that they own is not acting in their best interest in the first place?