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Unlawful Means: Contract, Tort, & Third Parties

Posted by Graeme Maitland — filed in Litigation

The unlawful means tort is the answer to the question of what does the Black Death, a cannonball, and a family squabble in New Brunswick have to do with a contract?

If you have a contract with someone, and they break it, you can sue them for breach of contract. But if a third party is the reason the contract was broken, what can you do?  You can’t sue them for breach of contract, they aren’t a party to the contract to begin with.   There is still a way for you to go after the third party using the unlawful means tort.

The unlawful means tort is a complicated and, until recently, ill-defined tort.  Even its name is not clear.  It’s been referred to as the tort of intentional interference with economic interests, interference with economic relations by unlawful means, tortious interference, interference with contractual relations, and so on.  For clarity, the Supreme Court of Canada simply refers to it as the “unlawful means tort”.

It evolved from the writ of trespass for abducting a servant which came about during the Black Death in England.  The premise is that it is illegal for A to interfere with C, a servant of B, to Cs detriment.  At that time, it was one wealthy person enticing a worker away from their job to work for them.  The original employer could not get compensation from the worker so this let get compensation from the new employer.

Over time, this law transformed into any unlawful interference by one party against another parties business interests. The clearest example is the 18th century case of two ship traders.  One fired a canon at a canoe full of natives who were trying to trade with another ship. By shooting at the canoe, the first trader was obviously interfering with the business of the other trader.


Unlawful Means and The Supreme Court


The Supreme Court of Canada dealt with this matter in the 2014 case of AI Enterprises Ltd. v Bram Enterprises Ltd. This was a property dispute between four brothers which led to one brother preventing the sale of a building for a higher price than what the building actually sold for.

Writing for a unanimous court, Cromwell J summed the tort up as follows: “the intentional infliction of economic injury on C (the plaintiff) by A (the defendant)’s use of unlawful means against B (the third party)”. Key to this is what sorts of conducts are considered ‘unlawful’ for the purposes of this tort. Cromwell J states that the conduct must give rise to a civil action by the third party or would give rise if the third party suffered loss as a result of it.  For economic harm to fall on C, the Court also says that A must have intended to harm C, either as an end in itself or as a means to an end.  It cannot be merely incidental.

If you have had a contract broken because of the actions of a third party, speak to one of the civil litigation lawyers at Aarbo Fuldauer LLP in Calgary.

Address: 3rd Floor, 1131 Kensington Road NW, Calgary, AB, T2N 3P4

Phone: (403) 571-5120

Email: [email protected]


The information in the blog is not legal advice. It should not be construed as legal advice and should not be relied upon as such.  If you require legal assistance, please contact a lawyer
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