Issue estoppel (LTB

TSL-87859-17 (Re), 2018 CanLII 121025 (ON LTB)

21. The HRTO order makes explicit findings about this issue and part of the remedy awarded is in relation to this issue. This issue is therefore barred by issue estoppel, which is a branch of the doctrine of res judicata.

22. Issue estoppel precludes a litigant from raising issues in a proceeding that were already adjudicated in a previous proceeding. The principles behind the doctrine of issue estoppel are that litigation should have finality (it should not be allowed to continue indefinitely), inconsistent results should be avoided, judicial resources should not be wasted on duplicative claims, and parties should not be permitted to harass one another with duplicative claims.

23. The criteria for issue estoppel, as per Richard A. Feldman in his Residential Tenancies, 9th ed. (Toronto: Carswell, 2009) at p.90, are:

i) the same question (issue) currently being advanced has already been decided in an earlier proceeding;

ii) that earlier decision was final; and

iii) the parties (or their privies) are the same now as in that earlier proceeding.

22. The criteria for issue estoppel are met here.