: Procedure — Class proceedings — Certification — Issue estoppel, functus officio — Motion to determine whether a fresh motion for certification may proceed — Remedial jurisdiction to re-open the certification motion — Preferable procedure and evidence “necessarily in issue” — Finality in the judicial system — Appeal dismissed Procedure — Res judicata — Issue estoppel — Danyluk conditions — Whether the first condition, the “same question”, was met — Preferable procedure and evidence required to establish it — “Distinctly put in issue and directly determined” and matters “necessarily determined” — Issue estoppel engaged — Appeal dismissed Procedure — Discretion — Setting aside issue estoppel — Whether discretion should be exercised due to material change in circumstances or new evidence — Reliance on alleged legislative and evidentiary changes in the CTA’s dispute resolution process — Potential injustice to class members weighed against finality — No palpable and overriding error — Appeal dismissed Evidence — A[...]