31 U.S.C. 711.
Each person having a claim or other rights assertable in the General Accounting Office may pursue such claim or right individually or through an attorney or other representative.
Any person who is a member in good standing of the bar of the Supreme Court of the United States or of the highest court of any State, territory, or the District of Columbia, and is not under any order of any court suspending, enjoining, restraining, disbarring, or otherwise restricting him in the practice of law, may represent others before the General Accounting Office.
In the prosecution of claims involving payments to be made by the United States, a proper power of attorney is required before an attorney or other representative may be recognized. A power of attorney from the principal may also be requested in other cases.
When an attorney acting in a representative capacity appears in person or signs a document submitted to the General Accounting Office in connection with a matter other than one involving a payment to be made by the United States, his personal appearance or signature shall constitute a representation that he is authorized and qualified to represent the particular party in whose behalf he acts. In the case of representatives other than attorneys, a simple written declaration from the principal will be accepted as evidence of the authority of the representative to act on behalf of the principal.
Prior to the conclusion of action by the General Accounting Office on a matter in which a principal is represented by another person whose authority to act is established under either § 11.3 or § 11.4, the principal may revoke the authority of his representative. Such revocation is not effective unless it is in writing and signed by the principal and until the written revocation is received by the General Accounting Office. Upon notification of the death of the principal during the pendency of any matter involving representation of the principal by an attorney or other party, the General Accounting Office will consider the representative's authority to have been automatically revoked.