To me, it's not as much of an ethical question as a practical one. Clearly there are other rights that ordinary citizens have, which people on parole don't have

To me, it's not as much of an ethical question as a practical one. Clearly there are other rights that ordinary citizens have, which people on parole don't have in the same way: freedom of association, freedom of travel, the right to purchase firearms, and so on. It's not—to me—ipso facto a violation of his constitutional right to free speech, though I'd definitely listen to the argument that it was. To me, it's a simpler question of whether this is a stupid thing to do, because his songs don't pose a danger, and time spent by pretending government employees are suited to evaluating rap songs and guessing whether they are going to lead someone to murder someone else is time wasted, that could be spent doing something more useful.