I'm not trying to muddy the waters on this issue or take a consequentialist perspective, but how is this materially different from someone rejecting oxygen?
The moral response seems to be to intervene rather than let someone commit suicide, regardless of how long it takes.
But we have to admit that ok, hanging yourself in your cell should be fine, because of this logic.
The reason it's not is political: looks a lot better to have somebody run a story "those horrible prisons are making prisoners eat!" than it is "two-hundred inmates supposedly hung themselves last year because they had the right to"
This is a political battle the prisoner is having with the jail: I am unhappy and ready to die. Make my life just a tiny bit more bearable or I will die in a way that makes you look bad.
I could go into a long rant about all the problems of the American system of jurisprudence. There are tons. We've lost our way on the reasons for prisons and the purpose of incarceration, amongst a lot of other related matters. I still think these folks should have absolute control over their bodies. If it looks bad? Well, it looks bad for a very good reason.
Political systems exist for political reasons. People forget that and ascribe all sorts of things to these systems they never deserved even when they were working well. We need a lot of reform. I wish these folks the best of luck.
Refusing food is less violent. Just like people have the right to refuse refuse to take medicine, refuse medical treatments etc, they should be able to refuse food.
