They could have acquired the right by prescription under the Prescription Act through more than 20 years use or they could have acquired it by the doctrine of Lost Modern Grant which is a legality whereby the access has been used for so long that it must’ve been granted at some stage but it was so long ago that the deed has been lost.
The end result is the same.
What they can’t do in the exercise of this right is become a nuisance which is what they are becoming from what you have said. They can’t also breach your privacy although how much it is breached is a matter of degree and it would be a very difficult action to bring.
If you lock the gate and give them a key, that is not unreasonable however you cannot get a court order to make them lock the gate and even if you could, enforcing it would be extremely difficult.
If for whatever reason, they are damaging something by virtue of the constant traffic, they are liable to pay for repairs under the doctrine of mutual benefit and burden which is the legal doctrine whereby if someone has the benefit of using something, they have the burden of maintenance.
If you simply lock to the gate but didn’t give them a key, they could take you to court to make you give them access and they could ask the court to award costs against you.
About the only action you could bring against them would be in action in private nuisance but even then, it’s not a particularly strong cause of action.
I wish I could give you a more favourable answer but that’s the situation.sorry.
Can I clarify anything for you?
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