Boundary disputes occur all too frequently. Sadly, a high proportion originate from poor-quality plans and careless conveyancing. The Court of Appeal decision in Ali v Lane [2006] EWCA Civ 1532; [2007] 02 EG 126 offers us a valuable lesson in the law and practice sector relating to boundary problems.
The general rule under the law is that it is not possible to refer to extraneous evidence to construe a written contract, but there are exceptions to this rule – boundary disputes are a prime example. Where the information in a conveyance is ambiguous, the courts can refer to extrinsic evidence, including subsequent conduct, if it is of probative value, to determine the parties’ intentions.
Having satisfied itself that this was a case in which it could use extraneous evidence as an aid to interpretation, the court went on to consider the evidential value of old Ordnance Survey (OS) maps, and of the position of roads, fences, hedges and trees. The court ruled that OS maps do not identify legal boundaries; they are designed to show physical features as they appear on the ground. Evidence of such features will not be relevant unless they existed at the time of the conveyance, or replaced or were otherwise related to physical features that did exist at the time.
The plan that caused the problem in Ali was drawn up in 1947. The errors in the plan were classic. The plan was drawn on a scale of 1:2500 and was too small to include detail that would have helped to establish the boundary line between the properties. One of the measurements had been wrongly transposed from one plan to another. There were also some simple omissions. The site of a potential access way should have been identified by coloured hatching and the position of a drain should have been indicated by coloured lines running between points marked A-B-C. However, neither of these was shown on the plan.
Anecdotal evidence suggests that errors such as this continue to cause a worryingly high number of professional negligence claims. How then can professionals avoid these problems? Adherence to the Land Registry’s rules regarding plans (set out in the Land Registry Practice Guide 40) would help enormously. Practitioners are used to proof-reading documents, but they should also check any plans in a document, cross-referencing them with the documents to which they are attached to ensure that they are properly edged, coloured and hatched, and that they contain all the information referred to in the accompanying conveyance or transfer.
In cases where a boundary dispute is unavoidable, practitioners should adhere to the Court of Appeal’s advice in Ali. They must regard themselves as being under a duty to ensure that clients are aware of the potentially catastrophic consequences of a dispute that could escalate out of all proportion to what is at stake. They must also draw their clients’ attention to the possibilities of alternative dispute resolution.
Allyson Colby is a property law consultant
