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 collapse.
  • 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 the Constitution.
      • They argued that it should only apply to subsidence damage on land that they didn’t have a property right to.
  • 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 compensation.
      • 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 homeowner.
    • 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.