Great care was taken to accurately reproduce the actual sites of the "Ripper" murders. Illustrations and actual photographs from 1888 were used. Similar care was used to reproduce the wounds inflicted upon the Ripper's victims.
Some real photos from the Ripper victims are pinned to the walls in the police station sets. Albert Hughes and Allen Hughes placed them there to unnerve the cast, so they'd give an edgier performance.
The crew built four blocks of Whitechapel on-location in Prague, including half a church.
In real life, Commissioner of Police Charles Warren never arrived at the site of the fifth murder because he'd resigned shortly before. Strangely, before his resignation, he ordered that no police officer was to enter a crime scene until he arrived, even though all of the previous victims had been killed on the street. No officer or investigator entered the building for three hours, because they were unaware of his resignation.
By not giving dates to specific scenes, the movie makes it seem that the Ripper murders, which occurred between August 31st and November 9th, 1888, happened in a much smaller timeframe. The investigation continued for many years.