Insurance company lawyers often try to use letters of protection against the injured party by insinuating that the doctor is biased because his bill is still outstanding.  Sadly, letters of protection would not even be necessary if the insurance companies paid the bills for the injured person from the git-go.   They put many people in a position where they have no choice but to seek help under a letter of protection and then they try to use the letter of protection to avoid responsibility for paying the bills at trial.