Getting benefit from someone else&#39;s property
<p>In a situation where one party receives incidental benefit from another party's efforts, if the other party suddenly changes course and causes the first one a harm, are there common laws or policies that would apply?</p>
<p>A little more specifically:</p>
<p>One neighbor has a backyard fence that forms a common barrier with the next neighbor.  That common barrier lets the neighbors both put their dogs outside securely.  The fence owner is not obligated to have the fence at all by municipal or neighborhood rules.  One day, the fence-owner suddenly decides to remove it without any advance notice, and the other neighbor's dog can't securely use the backyard anymore (or the dog even escapes!)</p>
<p>Does the fence owner have any duty to at least provide advance notice to his neighbor, <em>&quot;Hey, I'm going to remove the fence, it might affect your dog&quot;</em>?  Or are they truly free to take down the fence on a moment's notice, regardless of who might be negatively impacted?</p>
<p><em>(this is not a real situation.  This is loosely based on a real, but much more complex situation.  I didn't want to post the full details, because I'm not asking for specific advice, and because the full complexity of the real situation is a lot bigger.  I'm interested in the basic concepts in this hypothetical case)</em></p>

<h2>It depends; Permission may be Required</h2>
<p>This depends on both the facts on the ground, and the laws of the relevant jurisdiction. Residential fences are often governed by specific local laws at the municipal or county level in the US, so no generally applicable answer is possible, short of a book giving laws for each locality.</p>
<h2>Common-Law Rules</h2>
<p>Under the common law, followed by many but far from all US jurisdictions, the key question is whether a fence is a &quot;partition fence&quot; or not. A partition fence is one built on or near the property line that is owned jointly by the owners of the properties it divides.</p>
<p>A fence near the property line is probably a partition fence if:</p>
<ul>
<li>The two property owners jointly built or paid for the building of the fence;</li>
<li>Parts of the fence are on each side of the property line;</li>
<li>The owners have agreed that the fence is common property; or</li>
<li>Both owners &quot;use&quot; the fence, as by connecting it to another fence running in a different direction, or by relying on it to contain domestic animals.</li>
</ul>
<p>A Fence is probably not a partition fence if:</p>
<ul>
<li>It is entirely clear of the property line;</li>
<li>Only the owner on whose property it rests maintains it; and</li>
<li>Only the owner on whose property it rests uses it.</li>
</ul>
<p>The owner of one of the properties may not remove, demolish, or modify a partition fence without permission from the other. Removing or modifying a partition fence without the permission of the owner of the adjacent property is a tort, and can lead to damages for the value of the fence begin awarded.</p>
<p>The owners must each maintain a partition fence, often each caring for his or her side. Failing to do so may be a tort.</p>
<p>If a fence is not a partition fence, the owner of the land is also the sole owner of the fence, and may modify or remove it without permission from, or notice to, the owner of any adjacent or nearby property.</p>
<p>However, the above common-law rules may be modified by local laws, and one would be wise to check, or consult a lawyer who knows how to check, before making any demands.</p>
<h2>Sources</h2>
<ul>
<li>The page <a href="https://fences.uslegal.com/removal-or-destruction-of-fences/" rel="noreferrer">&quot;Removal or Destruction of Fences&quot;</a> from US legal reads:</li>
</ul>
<blockquote>
<p>A fence is an enclosure creating an adequate blockade around a particular land for the purpose of prohibiting intrusions from outside.  A landowner can remove a fence, separating his/her land from that of his/her neighbor, when such fence is located wholly upon his/her own land.  However, a landowner is not empowered to remove a partition fence without the adjacent landowner’s consent.  A partition fence is the joint property of adjacent landowners.</p>
<p>A fence erected on the line between the lands of adjoining owners generally belongs to the parties as tenants in common.  Generally, a partition fence is built equally on both sides of the line.  Until the contrary is shown, the partition fence is presumed to be the common property of both owners.  An owner of adjoining land can remove a partition fence upon formal notice to adjacent landowners.</p>
<p>For an improper removal of a partition fence, an aggrieved party can bring an action for damages.  The standard for measuring damages for such removal or destruction is its value at the time.  The value is determined by replacement costs minus depreciation for age and use.  Moreover, when someone builds a fence on another person’s land without any authority to do so, the landowner can remove or destroy such fence.  A person is liable for removing, destroying, or injuring a fence belonging to another person just as one who commits such acts against any kind of property belonging to another is liable[i].  Such person is considered a tortfeasor.  However, an individual cannot remove or destroy a fence on another individual’s land without his/her consent.</p>
</blockquote>
<ul>
<li>The page <a href="https://www.findlaw.com/state/maryland-law/property-line-and-fence-laws-in-maryland.html" rel="noreferrer">&quot;Property Line and Fence Laws in Maryland&quot;</a> from FindLaw reads, in relevant part:</li>
</ul>
<blockquote>
<p>Maryland doesn't have specific rules dealing with fences. Instead, the state follows the common law practice that a fence built along a boundary line is owned in common by both property owners when both use the fence, unless otherwise agreed. A property owner is said to use a fence when they &quot;hook-up&quot; to the fence with another row of fence, or keep animals in the enclosure created by the fence. A fence built and used only by the builder is that person's sole property. When you purchase a new home, you take a property with an existing fence built and used by prior owners. Simply put, if you buy a property with a co-owned fence, you likely need to continue your maintenance of the fence.</p>
</blockquote>
<ul>
<li>The page <a href="https://answers.justia.com/question/2019/05/28/is-it-legal-for-the-neighbor-to-remove-a-693710" rel="noreferrer">&quot;Is it legal for the neighbor to remove a fence on our shared property line?&quot;</a> from Justia's &quot;Ask a Lawyer&quot; feature reads:</li>
</ul>
<blockquote>
<p>If both landowners paid to install a fence directly on a property line in the past, then yes, they need your permission to remove or replace the fence. Many fences are not built on a property line, but are instead just on one property or the other.</p>
<p>If you have had your land surveyed, you may be able to determine your exact property line. You or your neighbor are free to build new fences without permission as long as neither the fence nor any construction or excavation encroaches on the other's property.</p>
<p>Fences are a common property dispute, and can have long term effects. If a fence encroaches significantly on someone else's land for many years, this can actually become the new legal property line in some cases.</p>
</blockquote>
<p>According to the &quot;Fences&quot; section of the page <a href="https://www.lawsociety.org.nz/for-the-public/common-legal-issues/disputes-between-your-neighbours/" rel="noreferrer">&quot;Disputes between your neighbours&quot;</a> from th New Zealand Law Society:</p>
<p>In New Zealand this is regulated by the  Fencing Act 1978. Except where modified by individual agreements:</p>
<blockquote>
<ul>
<li><p>Fences must be on the boundary line, though there is provision for give and take where the true boundary is difficult to fence.</p>
</li>
<li><p>The cost of building or repairing a fence is borne equally between adjoining owners, unless one owner damages it, in which case the cost of repairs will fall on that owner.</p>
</li>
<li><p>You can compel your neighbour to contribute to the cost of the fence bordering your two properties by following the procedures set out in the Fencing Act ...</p>
</li>
<li><p>Developers of new subdivisions usually exempt themselves from contributing to the cost of a fence.</p>
</li>
<li><p>Under the Property Law Act 2007, it is possible to apply to a District Court for an order to remove or alter a fence that is detrimentally affecting land or obstructing a view. Usually the cost of any removal falls on the person applying for the order.</p>
</li>
</ul>
</blockquote>
<ul>
<li>The Booklet <a href="https://Flsc.sa.gov.au/resources/FencesandtheLawBooklet.pdf" rel="noreferrer">&quot;Fences and the Law</a> from the  Legal Services Commission, South Australia states, on page 2:</li>
</ul>
<blockquote>
<p>Fences should be regarded as a joint
asset between neighbours. Even if your
neighbour has not paid for the fence they
are still a joint owner. This is because
a fence on the boundary is legally
considered to be part of the land on
each side.
If you intend to remove or alter an existing
fence, you should have your neighbour’s
permission or a court order. If you want to
put up a fence where there has not been
one before, your neighbour has a right
to object. It makes no difference if you
intend to pay the total cost</p>
</blockquote>

property