Pennsylvania Coal Co. v. Mahon
260 U.S. 393 (1922)
Pennsylvania Coal sold off
some deeds to land. But they only sold the surface of the land, and kept
the right to mine under the surfaces.
The deeds also gave
Pennsylvania Coal immunity for any damage caused to the surface from
their mining activities.
Pennsylvania has complex
property laws. Under Pennsylvania law there are three different layers of
property; the surface, the subsidence layer, and the coal layer. It's
possible to sell off one layer of property and keep the rest.
The subsidence layer is the
layer just under the surface where mining could cause the surface to
40 years later, Mahon owned a
home on one of the plots originally sold by Pennsylvania Coal. Mining was
causing subsidence and damaging Mahon's home, so he sued for an injunction.
The Trial Court found for
Pennsylvania Coal. Mahon appealed.
Mahon argued that
Pennsylvania had passed The Kohler Act (P.L. 1198),
which took away Pennsylvania Coal's mining rights.
The Kohler Act forbid the mining of coal in the subsidence
layer in such a way to cause damage to buildings on the surface.
Pennsylvania Coal argued
that if the Kohler Act were
applied in this case, it would be an illegal taking under
They argued that it should
only apply to subsidence damage on land that they didn't have a property
The Pennsylvania Supreme Court
reversed. Pennsylvania Coal appealed.
The Pennsylvania Supreme
Court found that the Kohler Act
was a legitimate exercise of the police power.
The US Supreme Court reversed
and found for Pennsylvania Coal.
The US Supreme Court found
that under the 5th Amendment, the
government has a right to take land, but it must be for the public good
and there must be compensation. The Kohler Act couldn't be a legitimate taking,
because there was no "public" good, and there is no
In fact, it was argued that
since the coal was valuable and supported many jobs, it was more in the
public's interest to mine the coal even at the expense of a single
The Court found that, while
property may be regulated to a certain extent, if regulation goes too far
it will be recognized as a taking.
In order to determine
whether or not the regulation goes too far, you have to look at the average
reciprocity of advantage.
Average reciprocity of
advantage basically says that the
aggregate amount of benefit that comes from a regulation is
approximately equal to the amount of burden the regulation causes.
Of course, you have to
consider the fact that the burden can completely fall on one person
and the benefits could fall on a different segment of the community.
The Court felt that since
Mahon only purchased the surface of the land, and had indemnified
Pennsylvania Coal from damage resulting from subsidence, he took a risk
and has to live with the consequences.
In a dissent, it was argued
that coal is, while in place, land. You aren't allowed to use your land to
create a nuisance, or disturb other
people's land. The government has a right to regulate public nuisances, so what's special about coal?
The dissent felt that the
restriction was not a taking at all but was instead a prohibition of a
noxious use, which is perfectly within the bounds of the law.
Pennsylvania Coal argued
that they had lost 100% of the value of the coal in the subsidence layer,
and a 100% loss was going too far. However, the dissent argued that they
hadn't lost 100% of their coal, they'd only lost a small percentage of
their coal since they still could mine all the coal in the lower layers.
The idea that losing 100%
of part of an investment is not the same as losing a small percentage of
the overall investment is known as conceptual severance.
The general rule for takings had been that permanent physical occupations
are always considered takings,
while nuisance control measures are never considered takings. But this
case modified the rule a bit. Here it was held that if the nuisance
control measure creates too much of a burden on the property owner, it is
considered a taking.
Although never overruled,
the Courts have been unable to develop any set formula for determining if
a regulation went so far as to be a taking.