Incorrect information about an alleged accomplice

Facebook and Twitter users have connected Marilou Danley, a woman whom law enforcement officials initially described as a “companion” of the gunman, with a viral video to suggest that she knew in advance the shooting would happen and was perhaps complicit in it. In the video, an unnamed concertgoer recounted her experience with two people who she said had told a group, “You’re all going to die,” before being escorted out of the concert.

There is no evidence in the video that Ms. Danley had been identified by the witness. The police have since said that Ms. Danley was out of the country at the time of the shooting and is no longer a person of interest.

Social media users falsely identify victims

As has become common in the aftermath of an event with unidentified victims, social media has been a tangled web of users expressing legitimate concern for missing loved ones and pranksters polluting social streams with fakery.

Several news outlets have done a fine job flagging fakes that include pranksters repurposing the photos of a German soccer player, a murder suspect in Mexico, a porn star and random social media stars. In a telling exchange, Gianluca Mezzofiere of Mashable reached out to the operator of one Twitter account sharing misinformation and reported the following:

Mashable reached out to the troll to ask why he’s spreading misinformation during such a critical time. “I think you know why,” he replied. “For the retweets :)” When Mashable pointed out that it’s unethical to spread misinformation when people are desperately looking for their missing family and friends, he just said: “You are right I’m sorry.” “Jack Sins” said he chose TheReportOfTheWeek (aka Reviewbrah) just because he’s a meme and tweeted Johnny Sins because he “is a living legend.” Asked whether he’s done it before and whether he’d do it again, he replied: “Yes and maybe.”

Las Vegas’ gun control laws cause confusion

Some inaccurate claims have popped up in post-shooting debates over gun control. Some are asserting that automatic weapons are “already illegal” in Las Vegas.

That’s not exactly true. To start, it’s not yet known what kind of weapons Mr. Paddock used. Police reports suggest he had at least 10. The rapid pace at which he fired has led to informed speculation that at least one weapon may have been fully automatic, like a machine gun. But nothing had been confirmed by the time these messages were posted to social media.

Also, while it’s true that a provision of the Firearm Owners Protection Act of 1986 banned civilian purchases of machine guns across the country, the provision also grandfathered in weapons that were made and registered before May 19, 1986. In response to a recent Freedom of Information Act request, the Bureau of Alcohol, Tobacco, Firearms and Explosives counted some 175,000 transferable machine guns in the national registry as of December 2015.