What is the legal test for a motion to disqualify an attorney from the Bar?

"Generally, a trial court's decision on a disqualification motion is reviewed for abuse of discretion. [Citations.] If the trial court resolved factual issues, the reviewing court should not substitute its judgment for the trial court's express or implied findings supported by substantial evidence. [Citations.] When substantial evidence supports the trial court's factual findings, the appellate court reviews the conclusions based on those findings for abuse of discretion. [Citation.] However, the trial court's discretion is limited by applicable legal principles. [Citation.] Thus, where there are no material disputed factual issues, the appellate court reviews the trial court's determination as a question of law. [Citation.] In any event, a disqualification motion involves concerns that justify careful review of the trial court's exercise of discretion." (People ex rel. Dept. of Corporations v. SpeeDee Oil Change Systems, Inc. (1999) 20 Cal.4th 1135, 1143-1144.)

"When the declarations submitted in connection with the motion to disqualify do not contain conflicting descriptions of the facts, an appellate court need not defer to the inferences drawn by the trial court in resolving factual disputes for which the parties did not submit direct evidence. [Citations.] In such a situation, the appellate court is concerned with the legal significance of the undisputed facts in the record and reviews the trial court's decision as a question of law. [Citation.]" (Faughn v. Perez (2006) 145 Cal.App.4th 592, 601.)

"`Ultimately, disqualification motions involve a conflict between the clients' right to counsel of their choice and the need to maintain ethical standards of professional responsibility.' [Citation.] . . . [H]owever, `[t]he paramount concern must be to preserve public trust in the scrupulous administration of justice and the integrity of the bar.' [Citation.] [] When disqualification is sought because of an attorney's successive representation of clients with adverse interests, the trial court must balance the current client's right to the counsel of its choosing against the former client's right to ensure that its confidential information will not be divulged or used by its former counsel." (City and County of San Francisco v. Cobra Solutions (2006) 38 Cal.4th 839, 846 (Cobra Solutions).)