Knowing your neighbour is now crucial thanks to the Court of Appeal's decision on failure of falcon breeding in West Cornwall says Lee Stutt

When Knowing Your Neighbour Becomes a Legal Liability: Thomas v Nicholas [2026] EWCA Civ 847

Where an important case gets reported just a few miles from us, we want to be one of the first on the scene. This is one, from West Cornwall, which upsets the previously understood duties that arise between neighbouring landowners. 

The Background

Mr Thomas is a smallholder in rural Cornwall. He owns land near St Just in Penwith, and his company, Upper Cot Estates Ltd, uses the adjacent ground for agricultural and associated purposes. In spring 2022, he and his team carried out some building work on that land: a barn was constructed, scaffolding was moved around, and at some point a digger was left parked near the boundary with his neighbours' property, with its bucket in the raised position.

Not the activities of a developer or industrial operator. Everyday realities of running land in the English countryside.

His neighbours, the Nicholas family, ran a different kind of operation. Through Raptors of Penwith Ltd, they bred high-value falcons for a Dubai-based investor. The Western Pens of their aviary sat close to the boundary with Mr Thomas's land. Breeding season ran from March to May. During that window, the Nicholas brothers said, the falcons were acutely sensitive to noise and visual disturbance. Three birds died, eggs were damaged, and they sued Mr Thomas for £258,500.

Round One: Nuisance Fails

The case went first to a High Court judge, who found in favour of the Nicholas brothers on both nuisance and negligence. Mr Thomas appealed to the Court of Appeal.

On the nuisance claim, Mr Thomas won, by a majority of two to one. The law of private nuisance, as recently restated by the Supreme Court in Fearn v Board of Trustees of the Tate Gallery [2023] UKSC 4, requires any interference to be assessed against the standard of the ordinary, average occupier of neighbouring land. The question isn’t whether the claimant's particular business was affected; it’s whether an ordinary person living or working next door would have had a legitimate complaint.

The majority in the Court of Appeal (Nugee and Moylan LJJ) held that the answer was no. Breeding falcons is not an ordinary use of land in the legal sense. It’s a specialist, sensitive operation that happens to be sited in the countryside. A neighbour doing building work, parking a digger, or shifting scaffolding would cause no material harm to the ordinary landowner's use of adjacent property. The falcon-breeding business was, in the terminology of the law, a "sensitive use," and the sensitive-use doctrine means that Mr Thomas owed no nuisance obligation to modify his ordinary activities for its benefit.

That conclusion had a long pedigree behind it. A Victorian case, Robertson v Kilvert (1889), established the same principle, in the context of paper stored in a warehouse that was vulnerable to mild heat: the paper merchant couldn’t sue in nuisance because the heat wouldn’t have affected any ordinary warehouse use. Mr Thomas's scaffolding and digger were analogous. They wouldn’t have troubled any ordinary neighbour.

Round Two: Negligence Succeeds (and This Is Where It Gets Complicated)

The Nicholas brothers also ran a negligence case alongside their nuisance claim, and here the Court of Appeal divided differently. Nugee LJ (with Whipple LJ agreeing) upheld the negligence finding, even after allowing the nuisance appeal. The damages award of £258,500 therefore survived.

The decisive fact was a series of WhatsApp messages exchanged in December 2020. Martin Nicholas had specifically told Mr Thomas that noise and visual disturbance near the aviary during the March to May breeding season could harm the falcons. That communication, the court held, changed the legal picture fundamentally.

Nugee LJ's reasoning ran as follows. The law of nuisance sets a floor of tolerance between neighbours based on what the ordinary occupier would reasonably endure. It does not, and never did, abolish the separate law of negligence. He found support in a Privy Council decision from 1902, Eastern and South African Telegraph Co Ltd v Cape Town Tramways, in which Lord Robertson had written: "all the remedies for negligence remain." That dictum had sat dormant in the case books for over a century. The Court of Appeal now gave it operational effect.

The duty of care that arose was carefully defined. It did not require Mr Thomas to stop working on his own land. It did not prevent him from building a barn, moving scaffolding, or using a digger. What it required, the court held, was that he carry out those activities in a manner that avoided unnecessary harm, provided an equally available alternative existed. The barn didn’t need to be built during the peak of the breeding season. The digger didn’t need to be parked next to the aviary boundary with its bucket raised. There was no operational necessity for either choice.

Why Mr Thomas Has a Legitimate Grievance

There’s real force in Moylan LJ's dissent, which would have given Mr Thomas a complete victory on both claims.

Moylan LJ's concern was legal coherence. The law of nuisance, calibrated over centuries and recently restated by the Supreme Court, was designed precisely to strike a fair balance between neighbouring landowners. One part of that balance is the rule that you can’t increase your neighbour's obligations simply by choosing to do something unusually sensitive with your own land. If Mr Thomas was free, in nuisance, to build a barn and park a digger without liability, it seemed to Moylan LJ to produce a contradictory result to say he was simultaneously liable in negligence for exactly the same acts.

He also raised a practical concern. Once a neighbour tells you about their particular sensitivity, does your legal position immediately change? Does the conversation create, in effect, a personal easement or restriction over your land, not entered into voluntarily and not recorded anywhere, simply because one neighbour happened to speak to another? Moylan LJ thought that was a troubling consequence, and that it would produce an "ever-changing kaleidoscope of duties" depending on what one landowner happened to know about another's activities.

From Mr Thomas's point of view, this isn’t merely an abstract legal argument. He received some WhatsApp messages about falcons. He didn’t enter into any agreement. He didn’t accept any restriction on the use of his land. He then carried out building work that any rural landowner might reasonably undertake. He is now liable for £258,500.

The Principle the Case Establishes

The majority's answer to Moylan LJ's concern was that the duty of care has hard limits. It’s calibrated to the defendant's actual knowledge, not to the full extent of the claimant's sensitivity. It doesn’t prevent ordinary activities; it regulates the manner, timing, and positioning of those activities where a less harmful alternative was genuinely available at no significant burden. And it is temporally bounded: the duty ran only from March to the beginning of May 2022, the period to which Mr Thomas's knowledge specifically related.

That limiting principle does real work, but whether it is sufficient to answer the coherence objection is genuinely contested. This was a court divided two to one on negligence, with the dissenting judge raising concerns that go to the heart of how neighbouring landowners should be expected to live alongside each other.

What This Means in Practice

The case has two main practical consequences.

First, for anyone operating a specialist or sensitive land use: proactively communicating your vulnerability to your neighbour in writing now has direct legal significance. It may not give you a nuisance claim (the Fearn objective standard remains the threshold for that), but it may establish the proximity and foreseeability required for a negligence claim if something goes wrong.

Second, for anyone doing ordinary things on their own land near a sensitive neighbour: receiving that communication is not a neutral event. It does not restrict what you may do, but it may restrict how and when you do it, if a less harmful alternative was available at the relevant time. That is a new and unsettled area of law, and the majority's approach in this case is likely to be tested further before it is settled.

The deeper question, which Moylan LJ posed clearly and which the majority did not fully resolve, is whether the law of negligence should be allowed to do indirectly what the law of nuisance deliberately chose not to do directly. That question will not go away, and it seems likely that the Supreme Court will eventually need to answer it.