Alexander Campbell from Wikipedia
Carbon County in the 1870s was no place for the meek. The flint hearted Protestant mine owners and the burly Irish Catholic miners were squared off over unionizing the coal fields. Both had blood on their hands. The Molly Maguires did their own violent deeds while the owners used the Pinkertons and the local law to terrorize the miners.
In 1877, four Molly Maguires were tried and convicted of murder in a trial in front of a kangaroo court. One of those condemned to die was Alexander Campbell, a hotel owner. As he headed to the gallows, he slapped his hand against the cell wall of the Carbon County jail and proclaimed his innocence, saying his handprint would stay on the wall forever to remind everyone of the injustice being carried out that day. It has.
Sheriffs have torn down the wall, painted over and scrubbed off the handprint. It keeps coming back. The jail is now a museum, and the cell is closed off. But if you peek through the iron door of Cell 17, you'll see the handprint. Campbell swore it would last as long as there was a jail, and he's been right so far.
The town was called Mauch Chunk then. It's Jim Thorpe now. The handprint is a famous phenomena, well represented on the web and written up by Matt Lake in Weird Pennsylvania and Patty Wilson in Haunted Pennsylvania among others.
Both branches of the Pennsylvania legislature passed resolutions condemning the trials of Alexander Campbell and the other accused Molly Maguires as being unconstitutional a couple of years ago. It was just a little late to be of any help to Campbell and the others who were executed on the infamous "Day of the Rope". His handprint still bears mute witness to that.