delivered the opinion of the Court.
In this original mandamus proceeding, we must determine whether a law firm should be disqualified from the underlying suit on the basis of a legal assistant’s work on the matter after previously having worked on the same matter while employed by opposing counsel. We have previously held that a firm can usually avoid disqualification when hiring an assistant who previously worked on a matter for opposing counsel if the firm (1) instructs the assistant not to work on the matter, and (2) takes other reasonable steps to shield the assistant from working in connection with the matter.
In re Am. Home Prods. Corp.,
Because the legal assistant’s employer did not take effective reasonable steps to shield the assistant from working on the case, and the assistant actually worked on the case at her employer’s directive, we hold that disqualification is required and direct the trial court to grant the defendant’s motion to disqualify and recuse plaintiffs’ counsel.
I
In the underlying case, the plaintiffs, Yvonne and Alberto Leal (“the Leals”), brought a medical malpractice suit against Columbia Valley Healthcare System, L.P., doing business under the name Valley Regional Medical Center (“Valley Regional”). Valley Regional filed a motion to disqualify the Leal’s counsel, Magallanes & Hinojosa, P.C., because of its employment of legal assistant Margarita Rodriguez.
Rodriguez had previously worked on the Leal case while employed by Valley Regional’s counsel, William Gault, at Brin & Brin, P.C., 1 assisting Gault from the inception of the suit. While employed by Brin & Brin, Rodriguez was a custodian of records and was responsible for filing many privileged documents concerning the suit, including investigative material, discussions with consulting experts, defense strategy, settlement negotiations, strategy for adding other parties to the suit, and attorney notes. Rodriguez also prepared correspondence to Valley Regional and its insurer. Before leaving Brin & Brin, Rodriguez signed a confidentiality agreement obligating Rodriguez not to work on any matter that she had previously worked on for Brin & Brin.
Approximately eleven months after leaving Brin & Brin, Rodriguez was hired by Magallanes & Hinojosa, a three-attorney firm, as a legal assistant for attorney J.A.
Despite the oral instructions from Ma-gallanes, Rodriguez had contact with the Leal file on a few occasions while working at Magallanes & Hinojosa. According to Rodriguez, her contact consisted of the following: (1) filing correspondence related to the Leal case; (2) rescheduling a docket control conference; (3) preparing an order and sending correspondence to counsel concerning a docket control conference; (4) calling Gault’s legal assistant regarding the docket control conference; (5) calendaring dates regarding the case on Magal-lanes’ calendar; and (6) making a copy of a birth certificate and social security card in the case at Magallanes’ directive on one occasion. When Magallanes learned that Rodriguez had scheduled the docket control conference, he again orally instructed her not to work on the case, and held a meeting where he informed both Rodriguez and Castro that they would be dismissed if this happened again.
After this admonition, Rodriguez had continued contact with the file, albeit marginally, filing correspondence for Magal-lanes and handling Magallanes’ calendar. Magallanes also directed Rodriguez to make a copy of a birth certificate and social security card in the Leal case in his presence on one occasion.
When Gault learned that opposing counsel employed Rodriguez, he filed a motion on Valley Regional’s behalf to disqualify and recuse Magallanes & Hinojosa as counsel for the Leals. The trial court held an evidentiary hearing at which both Ma-gallanes and Rodriguez testified. After the hearing, the trial court denied Valley Regional’s motion to recuse and disqualify Magallanes
&
Hinojosa, while ordering Rodriguez not to be involved in any of the cases on which she worked while at Brin & Brin. Valley Regional sought mandamus relief in the court of appeals, complaining that the trial court abused its discretion in denying the motion. The court of appeals denied the petition, concluding that Magal-lanes & Hinojosa “took sufficient precautions to guard against any disclosure of confidences by [Rodriguez].... ”
Valley Regional now petitions this Court for mandamus relief, urging that the trial court abused its discretion in denying the motion and that it has no adequate remedy on appeal.
2
Valley Regional argues that Magallanes & Hinojosa has failed to overcome the rebuttable presumption that confidences were shared, insisting that the informal screening done at the firm was ineffective to ensure Rodriguez did not
Magallanes & Hinojosa counters that (1) its screening measures were sufficient, and (2) the confidentiality agreement Rodriguez signed before leaving Brin & Brin adds an additional layer of protection against the sharing of confidential information. Magallanes & Hinojosa further suggests that Magallanes’ limited participation in the Leal matter, and Rodriguez’s minimal work on the case at Magallanes & Hinojosa, renders Rodriguez’s actual contact with the Leal file de minimis.
II
An attorney who has previously represented a client may not represent another person in a matter adverse to the former client if the matters are the same or substantially related.
Phoenix Founders, Inc. v. Marshall,
A nonlawyer employee who worked on a matter at a prior firm is also subject to an irrebuttable presumption “that confidences and secrets were imparted” to the employee at the firm.
Am. Home,
To determine whether the screening used by a firm is effective, we have said that the following factors may be considered: (1) the substantiality of the relationship between the former and current mat
disqualification will always be required under some circumstances, such as (1) when information relating to the representation of an adverse client has in fact been disclosed, or (2) when screening would be ineffective or the nonlawyer necessarily would be required to work on the other side of a matter that is the same as or substantially related to a matter on which the nonlawyer has previously worked. See ABA Op. 1526 at 3. Ordinarily, however, disqualification is not required as long as “the practical effect of formal screening has been achieved.”
Id.
at 835 (quoting
In re Complex Asbestos Litig.,
Here, there is no dispute that Magal-lanes & Hinojosa instructed Rodriguez not to perform work on any matter on which she worked during her former employment, including the Leal case. Thus, Ma-gallanes & Hinojosa satisfied the first prong in our disqualification analysis since it gave this instruction. Instead, the parties dispute whether Magallanes & Hinojo-sa took “other reasonable steps” to ensure Rodriguez did not work on the Leal case. Because we have not previously determined the types of “reasonable steps” necessary to avoid disqualification, we today take the opportunity to clarify the measures a law firm or lawyer must take to effectively screen a nonlawyer employee from a matter.
Ill
Disqualification of a party’s counsel is a severe remedy,
see Coker,
But where a serious conflict of interest is present because of a nonlawyer’s work on a matter that the nonlawyer previously worked on for opposing counsel, important public policies may balance in favor of disqualification. It is axiomatic that an attorney may not switch sides in the same matter, not only to protect the confidential information of a client but also to protect the integrity of the trial process and judicial system as a whole. Similar concerns about client confidentiality and the integrity of the legal system may arise where a nonlawyer employee is concerned. We have stated that “[t]he test for disqualification is met by demonstrating a genuine
threat
of disclosure, not an actual materialized disclosure.”
Grant,
With these principles in mind, we conclude that a simple informal admonition to a nonlawyer employee not to work on a matter on which the employee previously worked for opposing counsel, even if repeated twice and with threat of termination, does not satisfy the “other reasonable measures” a firm must take to properly shield an employee from the litigation. Instead the other reasonable measures must include, at a minimum, formal, institutionalized screening measures that render the possibility of the nonlawyer having contact with the file less likely.
This measure is necessary to ensure that the employee is fully and effectively screened from the matter and does not have contact with the forbidden file. If a firm has formal, institutional screening measures in place, all employees of the firm will have greater understanding of the firm’s expectations for guarding against conflicts of interest. We have previously suggested the necessity of formal, institutional measures,
see Grant,
Despite the screening measures used, if the employee actually works on the case at her employer’s directive, as happened here, and the employer reasonably should know about the conflict of interest, then the presumption of shared confidences must become conclusive. The Disciplinary Rules require a lawyer having direct supervision over a nonlawyer to make reasonable efforts to ensure that the assistant’s conduct is compatible with the professional obligations of a lawyer.
Phoenix Founders,
A law firm that directs a nonlaw-yer employee to work on a forbidden case and that reasonably should know about the conflict of interest is not strictly adhering to a screening process. When this happens, the threat that confidences will be shared becomes unduly high, and disqualification is required.
See Grant,
Similarly, the Restatement of the Law Governing Lawyers notes that “strict imputation” does not apply to nonlawyers who are employed by opposing counsel’s firm, but that the lack of imputation is inapplicable in a situation in which a non-lawyer employee is assigned at the new firm to work directly on the same matter on which the employee had worked at a prior firm. Restatement (Third) of the Law Governing Lawyers § 123 cmt. f (2000). While in the instant case Rodriguez was not actually “assigned” to work on the Leal matter, she was, on at least one occasion, directly given a task to perform on the matter. We fail to see a meaningful distinction between “assigning” a nonlawyer to a case versus having the nonlawyer perform work on the case with
In summary, when considering a motion to disqualify on the basis of a firm’s employment of a nonlegal employee who previously worked on the same or a substantially related matter for opposing counsel, the trial court must consider whether the hiring firm has rebutted the presumption of shared confidences. To rebut this presumption, the hiring firm must demonstrate that (1) the employee was instructed not to work on any matter which she worked on during her prior employment, or regarding which the employee has information related to her former employer’s representation, and (2) the firm took other reasonable steps to ensure that the employee does no work in connection with matters on which the employee worked during the prior employment, absent client consent. These other reasonable steps must include, at a minimum, formal, institutional measures to screen the employee from the case.
Despite the screening measures used, the presumption of shared confidences becomes conclusive if: (1) information relating to the representation of an adverse client has in fact been disclosed, (2) screening would be ineffective or the nonlawyer necessarily would be required to work on the other side of a matter that is the same as or substantially related to a matter on which the nonlawyer has previously worked, or (3) the nonlawyer has actually performed work, including clerical work, on the matter at the lawyer’s directive if the lawyer reasonably should know about the conflict of interest.
We do not believe these requirements will prove unduly burdensome for lawyers and their employees, even in the case of a small firm or sole practitioner. In the case of a small law office with only one employee, it may be that the lawyer will be required to perform some clerical functions on a matter from which the employee is screened. Yet this is a small burden when balanced against the threat of confidences being revealed and the protection of a client’s confidential information. In a small firm like Magallanes & Hinojosa that has more than one assistant, it will be a fairly simple matter to transfer all work on a forbidden case to the other employee and shield the screened employee from the case.
We finally note that these requirements apply only to nonlawyer employees who have access to material information relating to the representation of clients, as well as agents who technically may be independent contractors, such as investigators. See ABA Op. 1526.
IV
We agree with Valley Regional that Magallanes & Hinojosa failed to rebut the presumption of shared confidences since: (1) they did not effectively screen Rodriguez from the Leal matter; and (2) even if they had done so, Rodriguez actually worked on the Leal matter at Magal-lanes’ directive when Magallanes knew of Rodriguez’s previous work on the Leal matter. Magallanes instructed Rodriguez not to work on the Leal file, but did not take other institutional, formal measures to ensure Rodriguez did not work on the matter. For example, Magallanes & Hino-josa did not remove the file from Rodriguez’s access or provide Rodriguez with any written policy about conflicts of interest, relying instead on oral instructions that proved ineffective. Indeed, Rodriguez apparently had ready access to the file and performed work on it even after the admonition.
V
Magallanes & Hinojosa also contends that the confidentiality agreement Rodriguez signed on leaving Brin & Brin satisfies the additional reasonable measures needed to ensure confidentiality. We disagree. As we made clear in
Phoenix Founders,
it is incumbent on the hiring attorney to “take other reasonable steps to ensure that the [employee] does not work in connection with matters on which the [employee] worked during the prior employment, absent client consent.”
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Because the trial court abused its discretion in refusing to disqualify Magallanes & Hinojosa, we conditionally grant mandamus relief and direct the trial court to grant Valley Regional’s motion to disqualify and recuse Magallanes & Hinojosa from the Leal matter. We are confident the court will comply, and the writ will issue only if it does not.
Notes
. Attorneys from Brin & Brin, P.C. subsequently formed a new law firm called Vidaur-ri, Lyde, Gault & Quintana, L.L.P., where Gault now practices and represents Valley Regional in the underlying suit.
. Mandamus is available where a motion to disqualify is inappropriately denied as there is no adequate remedy on appeal.
See NCNB Texas Nat’l Bank v. Coker,
