18.—(1) This rule applies if—
(a)two or more cases have been started before the Tribunal;
(b)in each such case the Tribunal has not made a decision disposing of the proceedings; and
(c)the cases give rise to common or related issues of fact or law.
(2) The Tribunal may give a direction—
(a)specifying one or more cases falling under paragraph (1) as a lead case or lead cases; and
(b)staying (or, in Scotland, sisting) the other cases falling under paragraph (1) (“the related cases”).
(3) When the Tribunal makes a decision in respect of the common or related issues—
(a)the Tribunal must send a copy of that decision to each party in each of the related cases; and
(b)subject to paragraph (4), that decision shall be binding on each of those parties.
(4) Within 1 month after the date on which the Tribunal sent a copy of the decision to a party under paragraph (3)(a), that party may apply in writing for a direction that the decision does not apply to, and is not binding on the parties to, a particular related case.
(5) The Tribunal must give directions in respect of cases which are stayed or sisted under paragraph (2)(b), providing for the disposal of or further directions in those cases.
(6) If the lead case or cases lapse or are withdrawn before the Tribunal makes a decision in respect of the common or related issues, the Tribunal must give directions as to—
(a)whether another case or other cases are to be specified as a lead case or lead cases; and
(b)whether any direction affecting the related cases should be set aside or amended.