§ 623. Decisions final. 1. A decision of a referee, if not appealed
from, shall be final on all questions of fact and law. A decision of the
appeal board shall be final on all questions of fact and, unless
appealed from, shall be final on all questions of law.

2. No finding of fact or law contained in a decision rendered pursuant
to this article by a referee, the appeal board or a court shall preclude
the litigation of any issue of fact or law in any subsequent action or
proceeding; provided, however, that this subdivision shall not apply to
causes of action which (i) arise under this article, (ii) seek to
collect or challenge liability for unemployment insurance contributions,
(iii) seek to recover overpayments of unemployment insurance benefits,
or (iv) allege that a claimant or employer was denied constitutional
rights in connection with the administrative processing, hearing,
determination or decision of a claim for benefits or assessment of
liability for unemployment insurance contributions.