While I agree that the rights of the prisoner in the case you link to appear to be excessively curtailed , he was not "secretly imprisoned".
Secret imprisonment would be a clear indication of totalitarianism, but doesn't, as far as we know, appear to be happening on US soil.
For heaven's sake, if Guantanamo isn't a clear indicator to you, I doubt that secret imprisonment, when it comes or when it's proved to you, will be taken as a clear indicator either.
The people in Guantanamo are known to be there... albeit some of them shouldn't be.