You definitely don't want to leave anyone around who will tell stories that conflict with your version of events. And on the other hand, you can always find more people who will verify your version of events. For a reasonable price.
Lando: Ready to face justice, Chewie?
Chewbacca: I wish to state for the record that I am completely innocent of any wrongdoing. I have been nothing if not entirely loyal to the Rebellion.
Lando: You admitted you were a traitor!
Chewbacca: In a rhetorical point comparing myself to Princess.
Lando: No doubt the facts will come out in the trial.
Chewbacca: Of course there is nobody to verify my version of events here. I don't suppose you intend to try me without gathering all of the appropriate evidence?
Lando: Right, we'll have to go rescue Han.
Chewbacca: Tally-ho, then!
Lando: Just like old times!