Ethics

Plenty of authority holds you most notify a current client if you discover you have committed malpractice.  What about a former client?  For example, suppose you err in calculating interest owed on a claim your client won, so your client is shortchanged.  You catch the error only after the representation ends. 

One might say that at this point you owe your former client only a duty not to disclose or use confidences and therefore that you don't have to notify the former client.  (Better tell the carrier, though.)  That seems wrong to me, especially because the client will have suffered harm already and the representation is over, thus knocking out two possible grounds for tolling the SOL. I am not aware of any authority holding that you owe such a duty, however.

Thoughts?