Means of evidence

(1) The authority makes use of the means of evidence that it considers necessary, in the exercise of its due discretion, for ascertaining the facts. It may in particular 1. obtain information of every kind; 2. hear parties, examine witnesses and experts, or obtain the written or electronic statement of parties, experts and witnesses; 3. call for documents and files; 4. take a view of the object.
(2) The parties should cooperate in ascertaining the facts. They should in particular state facts and evidence known to them. A further-reaching duty to cooperate in ascertaining the facts, in particular a duty to appear in person or to make a statement, exists only insofar as it is specially provided for by legal provision.
(3) Witnesses and experts are under a duty to make a statement, or to render an opinion, where this is provided for by legal provision. Where the authority has engaged witnesses and experts, they receive, on application, compensation or remuneration by correspondent application of the Judicial Remuneration and Compensation Act.