Factual error: When reading out the list of the day's crimes, Artherton mentions two "teenaged" girls. Use of this term is not recorded in America until the 1920s and in Britain until the late 1940s. The series is set in 1889 and the speech used by the characters is consistently very much the speech of the time - it has not been updated for modern understanding.
I Need Light - S1-E1
Factual error: Inspector Reid calls Inspector Abberline "Chief Inspector." Frank Abberline was not promoted to Chief Inspector until 1890 but the episode takes place in 1889. (00:16:05)