... his new clone (5th one) proclaimed he could not be held responsible for any of the actions his former models had taken in the destruction of property, failure to return equipment etc.
"Only a despicable mutant traitor would suggest that the computer can't do something! Execute him!"
The premise of Paranoia is that the troubleshooters can’t win through their own actions. The Computer is the font of all beneficence from which all good things flow and everything that flows from the Computer is good. And everything from elsewhere is bad. Even if they are the same thing!
The player has put forward a perfectly sane and rational argument that limits the capability of the Computer to take action. Therefore it is insane and irrational by definition.