Issues related to the doctrine of res judicata are frequently involved in matrimonial actions and can result in disastrous consequences if overlooked by counsel. For example, in Boronow v Boronow, 71 N.Y.2d 284 (1988), a former wife who was a party to a concluded matrimonial action, and had a full and fair opportunity to contest property issues was barred by res judicata from a subsequent plenary action concerning title to the marital home which could have been, but was not, raised in the prior action. The Court of Appeals held that the courts and the parties should ordinarily be able to plan for the resolution of all issues relating to the marriage relationship in a single action.

However, in Chen v. Fischer, 6 N.Y.3d 94 (2005), it distinguished Boronow and held that a wife's subsequent personal injury action for intentional infliction of emotional distress and assault and battery was not barred by res judicata, although the allegations in the personal injury action were "virtually identical" to those in her counterclaim for divorce, and arose out of the same transaction or series of transactions. It reasoned that an interspousal tort action does not form a convenient trial unit with a divorce proceeding, and it would not be within the parties' reasonable expectations that the two would be tried together.