590.315—Witnesses.
(a)
The Assistant Secretary or presiding official may require that the direct testimony of witnesses in trial-type hearings be submitted in advance of the hearing and be under oath, and in written form.
(b)
Witnesses who testify in trial-type hearings shall be under oath or affirmation before being allowed to testify.
(c)
Witnesses subpoenaed pursuant to § 590.306 shall be paid the same fees and mileage as paid for like services in the District Courts of the United States.
(d)
Witnesses subpoenaed pursuant to § 590.307 shall be paid the same fees and mileage as paid for like services in the District Court of the United States.