There are more than 100 threads of evidence that link Leo Frank to the murder of Mary Phagan:
Only Leo Frank had the opportunity to be alone with Mary Phagan, and he admits he was alone with her in his office when she came to get her pay — and in fact he was completely alone with her on the second floor. Had Jim Conley been the killer, he would have had to attack her practically right at the entrance to the building where he sat almost all day, where people were constantly coming and going and where several witnesses noticed Conley, with no assurance of even a moment of privacy.
Leo Frank had told Newt Lee, the pencil factory’s night watchman, to come earlier than usual, at 4 PM, on the day of the murder. But Frank was extremely nervous when Lee arrived (the killing of Mary Phagan had occurred between three and four hours before and her body was still in the building) and insisted that Lee leave and come back in two hours.