In almost every settlement, there is an element of compromise. In some cases, there is "settlor's remorse" and one of the parties tries to rescind the agreement. Fortunately, the courts generally hold litigants to their bargains.
An example is Morant v. Sun Life Assurance Company of Canada, 2014 ONSC 2876 (S.C.J.). The parties attended a mediation where they reached a settlement. Approximately two weeks letter, the plaintiff's counsel wrote advising his client wished to resile from the settlement and would bring a motion to set it aside. Plaintiff's counsel filed an affidavit deposing that at the time of the settlement, the plaintiff was in emotional and physical pain, extremely fatigued and felt unduly stressed and pressured. The plaintiff herself did not file an affidavit.
Justice Daly dismissed the motion to set aside the settlement. Justice Daley held that as a general rule parties are held to their agreements, although there are certain situations where courts may exercise discretion not to enforce a settlement:
In the circumstances, there was no evidence that counsel did not have authority, that the plaintiff lacked capacity or that the settlement was unconscionable. At most, the plaintiff's evidence was that she had a change of heart or "buyer's remorse", which does not constitute proper grounds for setting aside a settlement.[34] As a general rule parties are to be held to their bargains and to settlements which they negotiate and conclude. The court may exercise its discretion not to enforce the terms of a settlement where there is evidence that:(a) the resulting agreement and settlement was unconscionable, fraudulent or based on a party’s misapprehension of a material fact which was known to the opposite party;(b) the solicitor representing the party was not retained or did not have authority to settle the action and this limitation was known to the opposite party; and(c) the party lacked the legal or mental capacity to enter into the settlement agreement at the material time.