What is the legal test for disqualifying an attorney from a separate employment application?

Corporations v. SpeeDee Oil Change Systems, Inc. (1999) 20 Cal.4th 1135, 1143.) "However, the trial court's discretion is limited by the 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." (Id. at p. 1144.)

"Depending on the circumstances, a disqualification motion may involve such considerations as a client's right to chosen counsel, an attorney's interest in representing a client, the financial burden on a client to replace disqualified counsel, and the possibility that tactical abuse underlies the disqualification motion." (People ex rel. Dept. of Corporations v. SpeeDee Oil Change Systems, Inc., supra, 20 Cal.4th at p. 1145.) When the issue raised is one of successive representations of adverse clients, the chief value jeopardized is that of client confidentiality. (Flatt v. Superior Court (1994) 9 Cal.4th 275, 283.) When the issue is simultaneous representation of adverse clients, the chief value at issue is that of attorney loyalty. (Id. at p. 284.) In either situation, the rules applied favor the first client represented. Thus, in cases of successive representation, "the need to protect the first client's confidential information requires that the attorney be disqualified from the second representation." (People ex rel. Dept. of Corporations v. SpeeDee Oil Change Systems, Inc., supra, 20 Cal.4th at p. 1146.) Similarly, in cases of simultaneous representation, courts protect the duty of undivided loyalty which the attorney owes the first client until the representation is complete. (Flatt v. Superior Court, supra, 9 Cal.4th at pp. 286-287.)" '[D]ecisions condemn acceptance of employment adverse to a client even though the employment is unrelated to the existing representation.' " (Id. at p. 287, italics added.)

Page 24