Why stop there?
What is the point of giving prisoners any privileges at all? Why is it that someone who has proven themselves incapable of being a member of society should be granted any of the comforts afforded by that society?
As far as i'm concerned, there is no such thing as a 'human' right. There are only civil rights, the rights granted to you as a citizen of society, as a signatory of the social contract. You agree to co-operate with your fellow man, working towards the betterment of society as a whole by playing your part as a cog in the engine, and treating other citizens as you would treat yourself. In return, society affords you certain privileges, like life, food, shelter, self-determination and employment. You are not deserving of these just because you are human. Drop a human in the middle of the Amazon jungle, without his society, and see how far he gets shouting 'i have a right to live'.
Now, when you break that social contract, you should be removed from society and from the privileges it grants you. You have shown you cannot hold up your end of the bargain. As someone who has proven that they are incapable of being a citizen, you should not for example be allowed to vote. You should certainly not be allowed to have conjugal visits, earn money, buy cigarettes or eat anything other than a basic protein-vitamin paste that sustains your nutritive needs. You should be made to understand that society gives you certain things on tolerance of your co-operation, and without society, without your fellow man, they would not exist. You should be made to understand the consequences of your actions. And after a time, if you have shown willingness and understanding, you may be allowed back into society.
And if you transgress again, that is it - no second chances. You are removed from society permanently, and placed in prison for life. End of story. If you cannot learn from your first mistake, then you are unable to be rehabilitated. Do not pass go, do not collect $200.
But instead, we have health spas that are stricter than prisons. Hell, there are play-schools that are stricter than prisons. We have prisoners who can pay someone R50 to let them escape, or pay someone R10 to bring a juvenile prisoner to their cell for 'entertainment'. We have prisoners who vote on who should rule the country, prisoners who can get a pizza ordered for them, prisoners who commit the same crime they were jailed for, the moment they are paroled. We have prisoners who are released for the president's birthday, who vow that if released the first thing they will do is go and kill someone, and who make good on that promise. We have murder and rape a common occurence in prison. And nothing changes.
You say you will curtail the privileges of rapists, of child abusers and mistreaters of women. I say what makes women and children so special that crimes against them are somehow worse than murder? Don't wimp out now - remove all privileges, from all prisoners, for all crimes. They have shown that they cannot abide by society's rules, now show them what society would be like if everyone behaved like them.