Colorado Court Rules
Colorado Rules of Professional Conduct
As amended through Rule Change 2018(4), effective March 15, 2018
(a) Except as stated in paragraph (d), a lawyer shall not represent anyone in connection with a matter in which the lawyer participated personally and substantially as a judge or other adjudicative officer or law clerk to such a person or as an arbitrator, mediator or other third-party neutral, unless all parties to the proceeding give informed consent, confirmed in writing.
(b) A lawyer shall not negotiate for employment with any person who is involved as a party or as lawyer for a party in a matter in which the lawyer is participating personally and substantially as a judge or other adjudicative officer or as an arbitrator, mediator or other third-party neutral. A lawyer serving as a law clerk to a judge or other adjudicative officer may negotiate for employment with a party or lawyer involved in a matter in which the clerk is participating personally and substantially, but only after the lawyer has notified the judge or other adjudicative officer.
(c) If a lawyer is disqualified by paragraph (a), no lawyer in a firm with which that lawyer is associated may knowingly undertake or continue representation in the matter unless:
1. the disqualified lawyer is timely screened from any participation in the matter and is apportioned no part of the fee therefrom; and
2. the personally disqualified lawyer gives prompt written notice (which shall contain a general description of the personally disqualified lawyer's prior participation in the matter and the screening procedures to be employed), to the parties and any appropriate tribunal, to enable the parties and the tribunal to ascertain compliance with the provisions of this Rule; and
3. the personally disqualified lawyer and the partners of the firm with which the personally disqualified lawyer is now associated, reasonably believe that the steps taken to accomplish the screening of material information are likely to be effective in preventing material information from being disclosed to the firm and its client.
(d) An arbitrator selected as a partisan of a party in a multimember arbitration panel is not prohibited from subsequently representing that party.
Cite as RPC 1.12
History. Entire Appendix repealed and readopted April 12, 2007, effective January 1, 2008; Comment  amended and effective July 11, 2012.
 This Rule generally parallels Rule 1.11. The term "personally and substantially" signifies that a judge who was a member of a multimember court, and thereafter left judicial office to practice law, is not prohibited from representing a client in a matter pending in the court, but in which the former judge did not participate. So also the fact that a former judge exercised administrative responsibility in a court does not prevent the former judge from acting as a lawyer in a matter where the judge had previously exercised remote or incidental administrative responsibility that did not affect the merits. Compare the Comment to Rule 1.11. The term "adjudicative officer" includes such officials as judges pro tempore, referees, special masters, hearing officers and other parajudicial officers, and also lawyers who serve as part-time judges. Paragraph III(B) of the Application Section of the Colorado Code of Judicial Conduct provides that a part-time judge "shall not act as a lawyer in a proceeding in which the judge has served as a judge or in any other proceeding related thereto." Rule 2.11(A)(5)(a) of the Colorado Code of Judicial Conduct requires a judge to disqualify himself or herself in a proceeding in which the judge served as a lawyer in the matter in controversy, or the judge was associated with a lawyer who participated substantially as a lawyer in the matter during such association. Although phrased differently from this Rule, those Rules correspond in meaning.
 Like former judges, lawyers who have served as arbitrators, mediators or other third-party neutrals may be asked to represent a client in a matter in which the lawyer participated personally and substantially. This Rule forbids such representation unless all of the parties to the proceedings give their informed consent, confirmed in writing. See Rule 1.0(b) and (e). Other law or codes of ethics governing third-party neutrals may impose more stringent standards of personal or imputed disqualification. See Rule 2.4.
 Although lawyers who serve as third-party neutrals do not have information concerning the parties that is protected under Rule 1.6, they typically owe the parties an obligation of confidentiality under law or codes of ethics governing third-party neutrals. Thus, paragraph (c) provides that conflicts of the personally disqualified lawyer will be imputed to other lawyers in a law firm unless the conditions of this paragraph are met.
 Requirements for screening procedures are stated in Rule 1.0(k). Paragraph (c) (1) does not prohibit the screened lawyer from receiving a salary or partnership share established by prior independent agreement, but that lawyer may not receive compensation directly related to the matter in which the lawyer is disqualified.
 Notice, including a description of the screened lawyer's prior representation and of the screening procedures employed, generally should be given as soon as practicable after the need for screening becomes apparent.