Title 9, Chapter 11, Section 43
(a) Evidence on trials. In all trials the testimony of witnesses
shall be taken orally in open court unless otherwise provided by
this chapter or by statute.
(b) Evidence on motions. When a motion is based on facts not
appearing of record, the court may hear the matter on affidavits
presented by the respective parties, but the court may direct that
the matter be heard wholly or partly on oral testimony or
depositions; provided, however, that this provision shall not limit
the right of parties to use depositions where they would otherwise
be entitled to do so.
(c) Determination of the law of other jurisdictions. A party who
intends to raise an issue concerning the law of another state or of
a foreign country shall give notice in his pleadings or other
reasonable written notice. The court, in determining such law, may
consider any relevant material or source, including testimony,
whether or not submitted by a party or admissible under the rules of
evidence. The court's determination shall be treated as a ruling on
a question of law.