32 CFR §776.46

1. (a)A covered attorney shall not act as advocate at a trial in which the covered attorney is likely to be a necessary witness except when:
   1. (1)The testimony relates to an uncontested issue;
   2. (2)The testimony relates to the nature and quality of legal services rendered in the case; or
   3. (3)Disqualification of the covered attorney would work substantial hardship on the client.
2. (b)A covered attorney may act as advocate in a trial in which another attorney in the covered attorney's office is likely to be called as a witness, unless precluded from doing so by § 776.26 or § 776.28 of this part.
3. (c)[Reserved]