(1) Any person entitled to request a trial under Article 124 (1) may intervene in the trial until the trial is completed.
(2) Any intervenor under paragraph (1) may continue trial proceedings even after the party in whose favor the intervenor enters the proceedings voluntarily withdraws his or her request for the trial.
(3) Any person who has an interest in the result of a trial may intervene in such trial to assist either party until the trial is completed.
(4) Any intervenor under paragraph (3) may participate in all trial proceedings.
(5) Where any cause for interruption or suspension of trial proceedings lies in an intervenor under paragraph (1) or (3), such interruption or suspension shall also effect the party in whose favor the intervenor entered the proceedings.