In Grant v. Thirteenth Court of Appeals, 888 S.W.2d 466 (Tex. 1994), the trial court disqualified defense counsel because it hired a secretary who had been employed by the plaintiffs' lawyer and had worked on the case.
Before the motion to disqualify was filed, the hiring firm became aware that the secretary had worked on the case during her previous employment, but simply instructed her not to discuss her prior work. She was not removed from contact with the case.
The court of appeals granted mandamus directing the trial court to vacate the order disqualifying the firm on the strength of testimony from the defense lawyers that the secretary had actually revealed no confidences to them.
The Supreme Court rejected the court of appeals' reasoning, noting the defense firm's lack of institutional procedures designed to guard against passage of information from employees who previously worked on matters adverse to firm clients.
Applying the rule that the threat of disclosure rather than actual disclosure is the basis for disqualification, the Supreme Court issued a conditional writ of mandamus directing the court of appeals to vacate its judgment.