The attack happened at the outdoor Xfinity Center in Mansfield, Mass.
Murphy allegedly fled, but was later arrested.
"Officers conducting the investigation were assisted by patrons that had been concerned and took photos and video of the assault on their cellular phones," a statement from the Mansfield Police said. "Those phones are being processed to recover the digital evidence of the assault."
Murphy pleaded not guilty to rape charges.
"This was a consensual act, not a sexual assault," Murphy's attorney, Neil Crowley told TMZ. "There are no allegations of force or violence against him. This was a private act that regrettably occurred in a public place. The young woman was neither intoxicated nor overcome by drugs at the time."