In our March 2025 newsletter we outlined the facts in the case Coster v Coster. We set out David’s first claim that his mother Robyn was estoppel from denying the existence of a common intention constructive trust. The second trust that David argued to support his claim of an interest in his mother’s property was a common assumption constructive trust.
This claim relies on an actual promise having been made by Robyn as to an interest in the land to be given to David rather than her acquiescence of an assumption she knew David held.
The courts have held that proving that the promise was made is not enough. There needs to be unconscionable conduct by the party who made the promise. To decide if there has been unconscionable conduct the court will look at the surrounding circumstances including the nature and character of the detriment, how it can be cured, its proportionality to the terms and character of the representation or promise and the conformity with good conscience. Actual knowledge of the detriment is not required.
His Honour held that David’s case fails.
Firstly, his Honour did not accept that the promise was made by Robyn. His Honour found that David would not have understood his mother to be saying anything other than that he would inherit the farm in her will if she still owned it.
As to whether David relied on the promise, assuming it had been made, His Honour found that there was no reliance. To prove reliance the affected party must prove that they would have acted differently in the absence of the promise or encouragement. His Honour found that David made his own choices through the years and his mother’s farm was a place he could fall back on if things did not work out. There was no evidence that, at any time David seriously committed to farming in reliance on the promise.
Based on the evidence His Honour held that it was not unconscionable for Robyn to assert her ownership of the Oakhampton.
The final argument put by David was that he was entitled to an interest in the land because of a joint endeavour constructive trust. To prove such a trust it was necessary for David to prove that there had been the formation of a joint endeavour between himself and his mother , the purchase of property pursuant to the joint endeavour and finally the premature termination of the joint endeavour, leaving his mother with a legal interest in the land that was not intended. His Honour commented that there is no doubt that David and Robyn, at times, farmed the properties together. However , he found that they did not enter into a joint enterprise. In 2002 when David claimed that the first promise was made David was at school and Robyn was still married to Alan. It is therefore unreasonable to think that she would entered into a joint endeavour agreement with David.
David’s claim for an interest in his mother’s property was dismissed.
This case highlights the need for careful documentation of promises and family arrangements in the hope of avoiding litigation.
