the jurisdiction… However, in order for the contract to be liable to be set aside there must be
circumstances which render it unconscionable for the party who seeks to uphold the contract to
have it enforced.”97 On the other hand, in the case of Australia Estates P/L v. Cairns City
Council98, the Queensland Court Of Appeal in Australia stated that Solle was overruled and that
Great Peace was persuasive. However, it is still doubtful as to which law Australia pays more
regard to.
The fact is that if Solle is solely followed with regards to common mistake, then the only remedy
available to parties would be that their contract can be voidable based on Lord Denning’s
formulation of the law. As discussed before, Lord Denning’s approach was very vague in not
providing much guidance to a court in determining when they can set aside a contract based on
common mistake. Thus, the courts will have a great amount of discretion in deciding when to
exercise this jurisdiction, which will lead to great uncertainty in the law. Thus, it is unwise for
Ireland and Australia to take this route in the law of common mistake.
In the Canadian case of Miller Paving Ltd v. B. Gottardo Construction Ltd.99 Goudge J.A.
expressed the view that Canada had adopted both the common law and equitable position on
common mistake. However in delivering his judgement he stated the following in relation to The
Great Peace doctrine:
“Great Peace appears not yet to have been adopted in Canada and, in my view, there is
good reason for not doing so. The loss of the flexibility needed to correct unjust results in
widely diverse circumstances that would come from eliminating the equitable doctrine of
common mistake would, I think, be a backward step.”100
Thus, it seems that Canada has rejected the Great Peace doctrine on common mistake because of
its inflexibility in its results. This is understood due to the high test that Great Peace laid out to
have a contract declared as void, which has proven almost impossible to satisfy. However, in
97
JohnW. Carter & David John Harland, Contract Law in Australia, 4th ed. (Sydney: Butterworths, 2002)
atpara. 1231.
98
[2005] Q.C.A. 328
99
(2007) 285 D.L.R. (4th) 568 (Ontario C.A.)
100
See Miller Paving, supra note 67 at para. 26.
72