I never understood why prisoners shouldn't at least have read-only access to the internet.
This is going to become a bigger issue as more and more people think and understand the world through Google searches and LLMs. One reason people who post bail end up with vastly better outcomes in court is because they can prepare for their cases so much better than those stuck in jail waiting for trial.
How does one setup a read-only access to the internet?
One doesn't "setup a read-only access to the internet". But for information access, I imagine something like Kiwix[1] or El Paquete Seminal (without the piracy of course)[2] would be useful to a lot of people
Another option would be to mitm all web requests from a custom web-browser (install a root cert on all devices) and drop all POST, PUT, and DELETE requests. Prohibit the browser from storing cookies or localStorage, and perhaps maintain an allow-list of sites which can be accessed.
This is obviously not foolproof, but it'd certainly make real-world "request smuggling" much more difficult.
Of course, a better question is if there's really even value to providing read-only internet access in the first place? I understand that for some inmates there might be concerns of them contributing to illicit operations in the outside world, but the rationale I usually hear for why inmates are prevented from computer/internet access has more to do with the "dangerous" information they might access (how to commit crimes in the future, avoid getting caught, etc). And I think both of these arguments are worth our skepticism.
[1]: https://kiwix.org/en/
[2]: https://en.wikipedia.org/wiki/El_Paquete_Semanal
It’s Semanal, not Seminal. Seminal amusingly translates to “related to semen”. Even more amusing when Paquete can also mean “crotch”.
Because their friends on the outside can give them information or instructions.
Killings of rival gangs in prisons for rewards etc
This happens anyways, though. And I have to imagine it is already fairly easy to tell someone in prison to do something of this nature, it's not a ton of information to convey, exactly.