Photographs taken by West showed Davis's blood on the grass.
West also took a picture of Davis in the emergency room, where he had five stitches on the back of his head.
The three arrested men were not talking to the press, but their friends were outraged.
Police said they were investigating the incident, but they were confident that the officers who responded to the party acted professionally.
New Hanover County District Attorney Ben David said that the DA's office is also investigating the incident.