“It was mind-boggling,” said Weatherly of the footage. “I can’t tell you how many times I’ve looked at it.”

Expectations were high going into the investigation, since the number of macabre artifacts present gave Weatherly and partner Dave Spinks reason to believe that there would be paranormal activity.

“With artifacts like that, there can be energies attached to them,” explained Weatherly.

“Personally, when we were there, we had some pretty crazy things happen.”

The executioner's table was dented with an apparent ax mark, and was stained by what looked like blood. Both Weatherly and Spinks agreed that the figure was likely the residual energy of the executioner's victims.

“That energy is stained on that table forever,” said Spinks. “All those people’s last moments of life are stained upon that table.”

Critics of SLS cameras are quick to point out that the complex algorithms that allow them to identify objects are far from perfect. The sophisticated technology is more than capable of picking up a shadow as a human, for instance, said Tim Farley, a computer software engineer and security analyst, in a 2014 interview with the online gaming site Polygon.

"Nobody trains those algorithms to detect ghosts; they're trained to detect people standing in front of it getting its attention," said Farley. "There are lots of things in frame that are invisible to a person and lots of ways [the SLS camera] can be fooled."