In Murphy v. Campbell, 964 S.W.2d 265, 271-72 (Tex. 1997), the plaintiffs filed suit against their accountants alleging the defendants gave them faulty professional advice. The plaintiffs further alleged that, as a result of this faulty advice, they were subjected to tax liability in a separate case against the IRS. The defendants moved for summary judgment based on, among other things, the statute of limitations. The plaintiffs responded, arguing their causes of action against the defendants did not accrue until their litigation with the IRS had concluded and their tax liability became fixed. The supreme court held that the plaintiffs' claims accrued not when their injury became certain, but when they should have known of their injury. Id. at 271. According to the supreme court, the plaintiffs in Murphy should have known of their injury no later than the date the IRS first issued its official deficiency notice to them. Id. This date preceded not only the resolution of the plaintiffs' claims against the IRS, but even the filing of the plaintiffs' suit against the IRS.