How would they go about making sure their victim is completely paralysed - from the neck down, certainly, unable to speak, and if possible unable to do anything but blink - but conscious and able to feel pain in all his body?
The state has to be permanent, and allow him to survive with contemporary medical technology and good care (in a German hospital) for about fifteen years.
I've googled all sorts of medical terms, but the requirement to preserve pain sensation stumps me.