Rule 1.08 Conflict of Interest: Prohibited Transactions
(h) A lawyer shall not acquire a proprietary interest in the cause of action or subject matter of litigation the lawyer is conducting for a client, except that the lawyer may:
(1) acquire a lien granted by law to secure the lawyers fee or expenses; and
(2) contract in a civil case with a client for a contingent fee that is permissible under Rule 1.04.