[adrianmonk]

Suppose there's a browser plugin that uses sentiment analysis on text fields to try to detect text written in anger. And it doesn't do anything with the information except warn you so you can think twice before posting an angry comment to social media or sending an angry email. Should that be illegal?

Or maybe it more directly tries to sense emotion by using your webcam to look at your facial expression.

[Hizonner]

> Should that be illegal?

That would be acceptable collateral damage, if it couldn't be permitted without opening the door for the creation of systems that used the information against the analyzed people's interests.

I'd be willing to at least consider a carefully crafted exception. The problem being that when you write such an exception, it tends to be awfully easy to introduce loopholes that, in practice, allow using uninformed pseudo-consent, or false consent with no real alternative available, to use information against people.

[PeterisP]

The thing is, if you include something like that (i.e. sentiment analysis as crude, rudimentary way of looking at people's emotions), the genie is out of the bottle - it's a widespread task that's used as a relatively simple homework excercise in undergrad courses, you would need to censor it out of textbooks worldwide, which is a quite big issue to say at least.

I.e. my point is that such a ban would have to be very extensive and invasive, with obvious censorship of small, simple segments of code and whole avenues of basic knowledge. Given some data, you can get a crude emotion detector from facial images or text messages - not state of art but somewhat accurate - with something like ten lines of code, with no previous skill on "emotion analysis", just applying generic ML approaches. I can't imagine how such a ban could be implemented, as so many people would still be able to easily make such systems whenever they wanted to, so the ban wouldn't be effective.

Perhaps you could regulate the application of automated decision making to decisions about people and requiring some review-and-override mechanisms (GDPR has some limited aspects of that), but it's a very different area than just banning knowledge and skills that already exist and are relatively widespread.