Should the client’s legal malprctice award be for the entire sum or should there be a deduction for the contingent fee the negligent attorney would have won?  The debate runs like this;  [For the full amount]  The client will have to hire a malpractice attorney to sue the negligent attorney, and will have to pay a fee, so why should the client have to pay twice.  When the contingent fee the negligent attorney would have won is deducted, the client never gets what he/she would have won had no mistakes been made.

[Against the full amount]  If the client was to et 2/3 of the award in the first place, and the attorney now said to be negligent 1/3, why should the client get a windfall when the first attorney is negligent?

Wyoming, in Horn & Horn v. Wooster & Duddy holds to the later argument.  "The Court stated they have clear authority regarding a prevailing party’s right to collect attorney’s fees from his opponent. In Wyoming the American rule is applied. The Court saw no reason for creating an exception to the American rule when legal malpractice was involved.
Some courts have ruled that a negligence attorney is not entitled to a deduction of his contingent fee from a malpractice award against him but, utilizing a quantum meruit theory, may be entitled to a deduction for the value of his services which benefited the client. The Court stated that using the above approach to calculate damages would be difficult because the facts would present nearly unlimited opportunities for the client to second-guess the first attorney’s tactics and work product. "