Premise: Mary Ann "Polly" Nichols (née Walker; 26 August 1845 – 31 August 1888) was one of the Whitechapel murder victims. Her death has been attributed to the notorious unidentified serial killer Jack the Ripper, who is believed to have killed and mutilated at least five women in the Whitechapel area of London from late August to early November 1888.
Hypothesis: Mary Ann "Polly" Nichols was definitely killed by Jack the Ripper.