Professional Responsibility

Former Client


  1. A lawyer who has formerly represented a client in a matter shall not thereafter represent another person in the same or a substantially related matter in which that person's interests are materially adverse to the interests of the former client unless the former client gives informed consent, confirmed in writing.
  2. A lawyer shall not knowingly represent a person in the same or a substantially related matter in which a firm with which the lawyer formerly was associated had previously represented a client
    1. whose interests are materially adverse to that person; and
    2. about whom the lawyer had acquired information protected by Rules 1.6 and 1.9(c) that is material to the matter; unless the former client gives informed consent, confirmed in writing.
  3. A lawyer who has formerly represented a client in a matter or whose present or former firm has formerly represented a client in a matter shall not thereafter:
    1. use information relating to the representation to the disadvantage of the former client except as these Rules would permit or require with respect to a client, or when the information has become generally known; or
    2. reveal information relating to the representation except as these Rules would permit or require with respect to a client.

The underlying question is whether the lawyer was so involved in the matter that the subsequent representation can be justly regarded as a changing of sides in the matter in question. Rule 1.9 Comment 2.

Based on whether there is a substantial risk that confidential factual information as would normally have been obtained in the prior representation would materially advance the client's position in the subsequent matter. Rule 1.9 Comment 3.

  • A lawyer cannot just not ask important questions to avoid conflicts.

A firm similarly cannot represent a client whose interests are materially adverse to those of a client represented by a former employee if it is a same or substantially related matter as the former if any lawyer remaining in the firm has confidential information material to the matter. Rule 1.10(b)

  • (This seems to be completely covered by Rule 1.9(a).)