Does anyone have reference to case law that supports that paying a debt does not, in effect, admit the account is yours?
I don't have case law,but if you can show it was under duress and that you paid under assumption it was your responsibility. Most settlement contracts would word it like there is no admission of account,but I am willing to resolve this matter between the two parties.
There is the equivalent of a "nolo" plea in court, neither admitting or denying fault. It depends upon what the circumstances are, there are plenty of sample letters which contain reference language stating you deny the debt, but are paying to settle just to avoid further inconvenience.
