It should be fairly easy to determine when the statute of limitations ends, no?  In legal malpractice, one must commence an action within three years of when the cause of action accrues, unless there continues to be "continuous representation."  When does the cause of action accrue?  This question remains thorny, and not always easily resolved.  Here, as an example is 730 J & J, LLC v Polizzotto & Polizzotto, Esqs. ;2010 NY Slip Op 00244 ;Decided on January 12, 2010 ;Appellate Division, Second Department  found that the statute had not expired some 6 years after the "error" and at least 5 years after another specified date that defendants argued was the start:
 

"Summary judgment based on the defense of the statute of limitations requires that a defendant make a prima facie showing that an action to recover damages for legal malpractice was filed more than three years after the cause of action accrued (see CPLR 214[6]; Rachlin v LaRossa, Mitchell & Ross, 8 AD3d 461), when "all the facts necessary to the cause of action have occurred and an injured party can obtain relief in court" (McCoy v Feinman, 99 NY2d 295, 301 [internal quotation marks omitted]). An action to recover damages for legal malpractice is deemed to accrue on the date the [*2]malpractice was committed, not when it was discovered (see Shumsky v Eisenstein, 96 NY2d 164, 166).

Under the doctrine of "continuous representation," the three-year statue of limitations for legal malpractice is tolled while the attorney continues to represent the client in the same matter in which the malpractice allegedly occurred, after the alleged malpractice is committed (Shumsky v Eisenstein, 96 NY2d at 168). The parties must have a "mutual understanding" that further representation is needed with respect to the matter underlying the malpractice claim (McCoy v Feinman, 99 NY2d at 306).

Here, the defendant failed to establish its prima facie entitlement to summary judgment dismissing the legal malpractice cause of action by demonstrating that the statute of limitations expired (see generally Winegrad v New York Univ. Med. Ctr., 64 NY2d 851, 853). Accordingly, the Supreme Court properly denied that branch of the defendant’s motion which was for summary judgment dismissing the complaint as time-barred without prejudice to renewal after completion of discovery.