43 C.F.R. § 4.232 Evidence; form and admissibility.
Title 43 - Public Lands: Interior
(a) Interested parties may offer at a formal hearing such relevant evidence as they deem appropriate under the generally accepted rules of evidence of the State in which the evidence is taken, subject to the administrative law judge's or Indian probate judge's supervision as to the extent and manner of presentation of such evidence. (b) The administrative law judge or Indian probate judge may admit letters or copies thereof, affidavits, or other evidence not ordinarily admissible under the generally accepted rules of evidence. The weight to be attached to evidence presented in any particular form is within the discretion of the administrative law judge or Indian probate judge, taking into consideration all the circumstances of the particular case. (c) Stipulations of fact and stipulations of testimony that would be given by witnesses were such witnesses present, agreed upon by the interested parties, may be used as evidence at the hearing. (d) The administrative law judge or Indian probate judge may in any case require evidence in addition to that offered by the interested parties.
Title 43: Public Lands: Interior
PART 4—DEPARTMENT HEARINGS AND APPEALS PROCEDURES
Subpart D—Rules Applicable in Indian Affairs Hearings and Appeals
Formal Hearings
§ 4.232 Evidence; form and admissibility.

