“Neither slavery nor involuntary servitude, EXCEPT as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.”
> Once you are in prison, choosing to work or not is a free choice.
It is literally not in California (though which work, within bounds that differ by prisoner, may be), and California this year defeated a ballot proposition which would have made your claim true.
The free choice is to whether commit or not the crime that puts you in prison. After that, until you pay your debt to society, the free choices are over.