Numerous news outlets reported yesterday the Parkland shooter was a member of a white supremacist organization. We decided not to report it because we felt it was suspicious, and it appears our suspicions were warranted. Here’s what happened. 
The first site we saw reporting the claim was the Anti-Defamation League, which quoted a white supremacist named Jordan Jereb. Jereb says he is affiliated with a Florida hate group called the Republic of Florida.
The ADL article also cited discussions about the shooter’s affiliation on the notorious trolling website 4chan.
Reviewing various discussions on 4chan throughout the day, a new picture began to emerge. Users began posting messages on how they were playing a prank on the media. 
Subsequent posts showed copies of private messages sent to 4chan members from ABC News requesting interviews about the supremacist group. 
Over the next several hours, more people on 4chan began to brag that the whole thing was a prank.
One user wrote, “it's all going according to plan. we sent them fake info so they would embarrass themselves. we even had a fake guy call them up to "confirm it". be ready to spread this around once they buy it. evidence will come soon.” 
It was around this time that articles about the supposed connection began popping up on various news sites. Almost all of them based their evidence on Jordan Jereb’s claim that he knew the shooter and had trained with him.
Jereb, who lives in Florida, describes himself as a "the right wing extremist nut." In 2016 he was charged with threatening an aide to FL Gov Rick Scott.
Jereb's group also had a toll-free, 24/7 phone number for people to call if they wanted to chat, making it very easy for anyone - including the media - to reach him.
By the afternoon, 4chan members were celebrating their prank, listing all the news outlets they had fooled. 
As the story continued to proliferate, the Tallahassee Democrat was the first to raise questions about the story, citing law enforcement sources who said they did not believe the shooter’s alleged connection to the white supremacist group was true. tallahassee.com/story/news/201…
By late afternoon, authorities in south Florida were asked about the connection during a press conference. Sheriff Steve Israel said he was unable to confirm a connection.
Eventually, the story began to fall apart. Jordan Jereb, the source of the original claim, walked it back and said he’d been “misunderstood.”
The Southern Poverty Law Center, which had also reported on the shooter’s alleged white supremacist connection, retracted their story. splcenter.org/news/2018/02/1…
As of this morning, numerous media outlets continue to report that the shooter is connected to a white supremacist group, despite the evidence suggesting the whole thing was a prank to trick the media.
Some of these outlets cite the original ADL article while others conducted followup interviews with Jordan Jereb. Additional news outlets cited each other’s coverage, creating a feedback loop of questionable reporting.
There are many lessons to be learned here, perhaps the biggest of which is that you probably shouldn’t use notorious pranksters like 4chan as your source.
But it also is a cautionary tale of what happens when news orgs compete for the latest scoop and are prepared to believe claims from a single source, esp one that is clearly seeking attention.
To be clear, all of this does not mean that the shooter did not espouse extremist views. Numerous interviews with students who knew him cite examples of extremist and Islamophobic statements, which should be investigated further.
But making the jump from his alleged extremist views to him being a member of a white supremacist group appears to have been a serious error by numerous media outlets.
