Gisela Aguilar
February 17, 2024
LAW 402B
Class 21 Case Brief
Pennsylvania Coal Company v. Mahon
Facts:
A property owner sued to prevent the Pennsylvania Coal Company from mining beneath their
property. The mining activity would remove supports, leading to subsidence of the surface and
houses. However, the deeds to their homes only conveyed surface rights, and the right to remove
coal beneath their homes was a separate estate. The Kohler Act prohibited companies in
Pennsylvania from mining coal in a way that would cause subsidence of dwellings and the
surface.
Issue:
Did the statute allow the use of eminent domain, and if so, was just compensation required?
Rule:
The government may regulate property, which is not a taking, but overregulation will
constitute a taking, which requires just compensation
Analysis:
The case established the regulatory takings doctrine initially, but more recent tests have replaced
it. The case dealt with the question of when a regulation goes too far. To determine this, the
diminution-in-value test involves assessing the regulation's financial impact on the property's
value.
Conclusion:
The court ruled that public subsurface rights cannot be taken without compensation.
