Two armed robberies which occurred within two weeks of each other. Three Drexel University students were walking and a man alleged to be D, approached the women, drew a black handgun approximately 6-8 inches in length, cocked it, and demanded that the women give him their money. After the women explained that they had no money, the assailant demanded their cell phones. Each complied, giving the man their cell phones and digital cameras. The victims immediately went to campus security who escorted them to a police station to provide a statement and identify their assailant. Two days later, they viewed two photo arrays. Each photo array was composed of eight individuals. Included in the photo arrays were D, along with another suspect, and other individuals closely resembling D and the other suspect. The three victims were separated and provided a photo array one at a time. Two victims identified d out of the photo arrays. Three months later, on January 18, 2006, the third identified D in an in-person lineup. The second robbery occurred against University of Pennsylvania students. A man alleged to be D and a co-conspirator walked toward the students. As the men approached the couple, D separated from his co-conspirator and flashed a silver handgun, approximately 6-8 inches in length. The woman began to scream. D threw her to the ground and ordered her to be quiet. At the same time, D's co-conspirator threw the male down onto steps of a nearby residence. The men demanded whatever the victims had. The couple gave them everything. The woman continued to cry and scream, and, so, D repeatedly struck her on the back of her head with his gun. D and his co-conspirator eventually fled the scene. The couple gave their account of the events and described their assailant to Detective Lydon of the University of Pennsylvania police department. The Detective separated the victims and showed three separate photo arrays of individuals that had similar characteristics to D. The woman identified D in the second array. The same procedure was conducted with the male and he pointed out D from the array but was less than 100% positive. The sole evidence connecting D to the robberies was eyewitness identification by the victims. D filed a pre-trial motion in limine to present the expert testimony of Dr. Solomon Fulero regarding the fallibility of human memory, the science as to human recall, and scientific studies related to the reliability of eyewitness testimony generally. The court denied the motion and a motion for a Frye hearing. D was convicted on one of the crimes and appealed. The appeals court affirmed. D appealed.