Mercy Moment Murder Measure - S1-E7
Factual error: Early in the episode, there is a long shot of Woodhull's farm, snow on the ground...and aeroplane vapor trails in the sky.
Factual error: Helmuth von Moltke is addressed and referred to several times as Field Marshal. He wasn't promoted to that rank until 1871. He was a lieutenant-general during the Second Schleswig War in 1864.