Imputed disqualification generally occurs when an entire firm (private law firm, corporate/organization legal department, or legal services organization) is barred from representing a client because one or more of its lawyers is personally disqualified from representing that client because of a conflict of interest. Imputed disqualification is governed primarily by state codes of conduct for attorneys, which vary by state.
A firm’s imputed disqualification often exists because one of the firm’s current members became disqualified while associated with the firm. However, an individual lawyer’s disqualification may at times be imputed to a firm when that lawyer becomes associated with the firm, and may even after the personally disqualified lawyer has left the firm. Imputed disqualification that arises within a continuing association of lawyers may be cured by a client's consent, and a firm may erect an “ethical screen” to prevent the exchange of client confidences between a newly hired lawyer and the rest of the firm. Such “ethical screens” have traditionally been allowed with new lawyers joining a firm from government service. Similarly,a personally disqualified lawyer may avoid imputed disqualification upon leaving a firm by proving that no protected client confidences were exchanged between the departed lawyer and any of the lawyers remaining with the firm.