Chicago police have now arrested two suspects in the brutal sexual assault of a 15-year-old girl that was streamed on Facebook Live. Both of those charged in the attack are teenage boys, ages 14 and 15, and police continue to look for more accomplices.

About 40 people may have watched the rapes on Facebook as they happened, but none of them reported the crimes to the police. That's raising ethical and legal questions about those who witnessed the crime, including whether they can be charged for their inaction.

Chicago Police say the 15-year-old victim knew one of her attackers and was lured by him to a home on the city's West Side.

"From there, she was not allowed to leave and she didn't consent to what occurred," said Chicago Police Commander Brendan Deenihan.

As many as six attackers brutally raped the girl.

"Due to the graphic content that I observed, I don't want to go into the detail of what was on the video, " says Chicago Police Superintendant Eddie Johnson. "But I want to tell you, the young men responsible — they should be ashamed of themselves. They've humiliated themselves, humiliated their families, and now they're going to be held accountable for what they did."

They'll be held accountable, Johnson says, because some of the suspects shot video of the vicious assault, and one streamed it live on Facebook, where about 40 people watched.

"We've seen a couple acts in this city now in the last few months involving social media, and it just disgusts me that people would look at those videos and not pick up the phone and dial 911," says Johnson. "It makes you wonder, where are we going, what are we doing as a society?"

The victim is "extremely traumatized," says Cmdr. Deenihan — so much so that she can barely even talk to investigators about what happened.

"We obviously have a video of the incident, so we have verifiable, objective evidence of what occurred to this young lady, but she's just having a very difficult time," says the commander. "And then on top of it, constant social media bullying ... people are really making fun of the victim and just a lot of off-color comments about what occurred, and now this is causing a lot more trauma to this victim."

The attack happened March 19, the day her mother reported her missing. The next day, a relative of the girl said a teen in the neighborhood alerted him to video of the incident on Facebook. He took took screen shots of the attack to the girl's mother, which she took to police.

Community activist Andrew Holmes says he was able to track down the full video and turn it over to police. He says he thinks anyone who viewed the gang-raping of the girl and did not report it should face criminal charges themselves.

"If they can look at this sexual assault and torture take place ... it tells me they really don't give a damn, you know, what happens to a human being out here," Holmes says. "You got over 40-some people watching it, and enjoying it. ... I mean, it's your responsibility to turn that footage over. On the other hand, what if it was your daughter?"

Legal experts say it would be very difficult to prove criminal charges against someone who views a crime on a live stream and doesn't report it.

"Generally, ordinary citizens are not legally required to report a crime or to do anything to stop it," says Stephanie Lacambra, criminal defense attorney at the Electronic Frontier Foundation, an organization that defends people's constitutional rights and civil liberties in the digital world. "There is no general duty to be a good Samaritan."

There are some exceptions, though. Many states require people in certain jobs and fields to report suspicions of child abuse and some other crimes, so Lacambra says prosecutors would have to prove "that the charged individual has some specific duty to report a particular incident in the first place that was recognized by law."

But witnessing an alleged crime in the digital space is even more nuanced that witnessing in person.

First of all, "how do you prove that the individual whose account was used to view a stream was in fact the person who viewed it?" asks Lacambra. Secondly, she says prosecutors would have to prove that the individual watching the video knew what they were seeing was both real and a crime.

"The public generally should be more skeptical about what they view on the Internet, because it's not a direct eyewitness account," says Lacambra. "It's like reading an article and trying to discern if it's true or fake news — you don't know if the video you're watching has been photoshopped or if the details you're viewing are in fact true."

Lacambra says there could be jurisdictional issues, too, if the alleged crime takes place in one state or country but is viewed in another.

Law Professor Allen Shoenberger at Loyola University Chicago agrees that there is no general rule requiring viewers of a crime on a live stream to report it — but says that in this case, because the victim is 15, child pornography laws may apply.

"The federal statute, for example, makes it quite clear that possessing those images is grounds for culpability, criminal culpability," says Shoenberger. "Just watching them is grounds for criminal culpability."

And Shoenberger says anyone pressing the "like" button or commenting in a way that could be construed as encouraging or promoting the rape could be charged with aiding and abetting the criminal act — though he acknowledges it could be difficult to prove that the viewer knew the victim was underage.

The two teenagers arrested in the case both are charged with manufacturing and distributing child pornography, in addition to being charged with aggravated criminal sexual assault, the statute for rape in Illinois.

"I guess they deserve what they get by doing this really stupid act of showing criminal acts, by recording it or transmitting it," says Shoenberger. "It's just unbelievably imbecilic."

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