"We certainly recognize that the video, photograph, alleged facts, and surrounding circumstances set forth on the Internet and portrayed in the media would cause even the most optimistic of man to call into question the defendants' presumption of innocence," Duncan said in the Jan. 9 statement.
"We must be careful in this age of social media to ensure that the words set forth do in fact portray the actual story," he said.
The 12-minute video shows a student who was not involved in the attack but apparently aware of it joking about it while others in the background chime in.
In a photograph, the two defendants are apparently seen carrying the girl by her arms and legs, according to the transcript of an October hearing where a judge heard testimony before deciding whether the teens should be charged.
At that hearing, three other high school students testified to seeing the attack on the girl from nearby Weirton, W.Va. Two of those students also recorded a video and photograph of the attacks on their phones, but deleted the images shortly afterward. Those students were told at the hearing that they would have been charged had investigators found the images.
In letters to attorneys for each of the three students last fall, prosecutors said that while each student "may not have conducted himself in a responsible or appropriate manner, his behavior did not rise to the level of criminal conduct," according to copies of the letters obtained by The Associated Press through a records request.
Prosecutors added in each case that, "we will not prosecute your client for his actions" on the weekend of the alleged attack in August, the letters said.