Great 8, Number 8: Pennsylvania Coal v. Mahon

by: Joseph Grather
17 Mar 2023

For the final case in my “Great 8”, who else but Holmes?

Before we get there, a quick caveat on “great cases” (from Holmes):

“Great cases like hard cases make bad law.  For great cases are called great, not by reason of their real importance in shaping the law of the future, but because of some accident of immediate overwhelming interest which appeals to the feelings and distorts the judgment.  These immediate interests  exercise a kind of hydraulic pressure which makes what previously was clear seem doubtful, and before which even well settled principles of law will bend.” Northern Securities Co. v. United States, 193 U.S. 197 (1904)(Holmes, J., dissenting). 

So, best for last? Pennsylvania Coal v. Mahon (1922). The case’s hundredth-year anniversary was well-documented by our colleague, Robert Thomas, on his lively blog. The case has been the subject of law review articles, blogs, and, of course, hundreds of case citations.

I still remember the day we studied the case in Property 2 (twenty-five +/- years ago)… and somehow the words still resonate in my mind today: ‘Government could hardly go on, if, to some extent, values incident to property could not be diminished without paying for every such change in the general law… But if government regulation goes too far, it will be recognized as a taking.’ ( from memory, but I think it’s pretty close).  So, for the last century, courts and practitioners have been trying to figure out what “too far” means. 

Perhaps the most convoluted “too far” test spawned from the dissenting opinion in Mahon is Penn Central (speaking of hard cases), but that’s a whole blog topic in itself.

I’m sure all of you have read Mahon, but read it again. And, if you’ve never read it, accept this blog as your invitation.  Suffice it to say, it is the genesis of regulatory takings jurisprudence, and the property owner won!

And now if you’ll excuse me, I’m off to find a four-leaf clover….

Happy Saint Patrick’s Day!