The Historical Development of the Law Regarding Vicarious Disqualification: Generally speaking, the California State Bar's Rules of Professional Conduct govern attorney discipline; they do not create standards for disqualification in the courts. (Hetos Investments, Ltd. v. Kurtin (2003) 110 Cal.App.4th 36, 47.) Courts analyzing questions of disqualification often look to the Rules of Professional Conduct for guidance. California Rules of Professional Conduct, rule 3-310(E) provides: "A member shall not, without the informed written consent of the client or former client, accept employment adverse to the client or former client where, by reason of the representation of the client or former client, the member has obtained confidential information material to the employment." While the Model Rules of Professional Conduct promulgated by the American Bar Association (ABA) address the issue of vicarious disqualification (see ABA Model Rules Prof. Conduct, rule 1.10), the California Rules of Professional Conduct do not. Thus, in California, vicarious disqualification rules are the result of decisional law. (City and County of San Francisco v. Cobra Solutions, Inc. (2006) 38 Cal.4th 839, 847.) It is useful for our analysis that we first discuss the development of California law in this area in some detail. In William H. Raley Co. v. Superior Court (1983) 149 Cal.App.3d 1042, the court concluded that "automatic or mechanical application of the vicarious disqualification rule can be harsh and unfair to both a law firm and its client." (William H. Raley Co. v. Superior Court, supra, 149 Cal.App.3d at p. 1049.) Instead, the court reasoned that "the better approach is to examine the circumstances of each case ..." in light of the applicable competing interests. (Ibid.) "The court must weigh the combined effect of a party's right to counsel of choice, an attorney's interest in representing a client, the financial burden on a client of replacing disqualified counsel and any tactical abuse underlying a disqualification proceeding against the fundamental principle that the fair resolution of disputes within our adversary system requires vigorous representation of parties by independent counsel unencumbered by conflicts of interest. In a case such as this the court also must consider in favor of disqualification the disruptive effect of repeated disqualification proceedings on the administrative process of the court and the financial burden of such proceedings on the moving party." (Id. at p. 1048.) In very brief summary, the history of the law of vicarious disqualification appears to be as follows: (1) appellate courts initially concluded vicarious disqualification was not automatic, but instead subject to a balancing test; (2) Henriksen v. Great American Savings & Loan (1992) 11 Cal.App.4th 109, concluded the burden of rebutting the presumption of imputed knowledge simply could not be satisfied in the case of a tainted attorney who represented one party and switched sides in the same case; (3) the Supreme Court favorably cited Henriksen and appeared to state a rule of automatic vicarious disqualification any time material confidential information was presumed to be held by the tainted attorney (Flatt v. Superior Court (1994) 9 Cal.4th 275); (4) the Supreme Court subsequently suggested that whether vicarious disqualification can be avoided by a proper ethical wall was still an open question (People ex rel. Dept. of Corporations v. SpeeDee Oil Change Systems, Inc. (1999) 20 Cal. 4th 1135); (5) the Supreme Court has never directly addressed the issue on the merits.