In Texas, two doctrines toll the limitations statute on malpractice.

   1.  the discovery rule -- that a causes of action does not accrue until the plaintiff knew about the wrongful act and resulting injury or could have known with reasonable diligence.  E.g., Murphy. Campbell, 964 SW2d 265 (TX 2001).

    2. equitable tolling -- a court can consider equitable justifications and policy considerations.  E.g., Apex Towing Co. v. Tolin,  41 SW3d 118 (Tex 2001) holding that in litigation cases the statute of limitations on a malpractice claim against that attorney is tolled until all appeals on the underlying claim are exhausted or the litigation is finally concluded.

Generally the equitable tolling rules does not apply to malpractice claims based on errors committed by attorneys in the course of conduction transaction work.  The Apex Towing doctrine is based on the idea that it would be inconsistent to encourage malpractice claims instead of concluding the underlying litigation first.