Tommaso De Benedetti nearly fooled me. Twice.

This is what Bashar al-Assad’s fake Twitter account now looks like. (Twitter)

In an interview with the Guardian today (one of the news sites the teacher fooled), De Benedetti said he posed as high-profile people on Twitter to expose weaknesses in the media. “Social media is the most unverifiable information source in the world but the news media believes it because of its need for speed,” he told the Guardian.

One of the handles De Benedetti has tweeted as is @presMarioMonti, which purports to belong to the Italian prime minister.

“The news of the death of Fidel Castro has been confirmed to me by EU vice president Olli Rehn,” the supposed Monti tweeted in January.

The fake news of Castro’s death went viral, and the Cuban government blamed the rumor on a hapless Madrid man, who happened to retweet the news.

In his earlier life, De Benedetti tricked Italian newspapers into publishing fake interviews with writers, a ruse for which he was eventually caught, the Guardian reports. But his efforts online seem to have reached — and fooled — far more people.

De Benedetti’s first foray into Twitter was to pose as a Swedish writer, but he soon escalated his efforts to impersonations of world leaders. He also set up a Twitter account for the Vatican’s number two, from which he sent a fake announcement of the pope’s death, according to the Guardian. “It’s so easy,” he told the news site of his impersonations.

Hoaxes are so easy. I learned that the hard way last year in the months after I interviewed the alleged Amina Arraf, a gay Syrian girl living in Damascus, in April. In early June, my colleague Melissa Bell and I helped reveal that Amina was actually Tom MacMaster, a 40-year-old American man from Georgia. It had all been a hoax.

The story didn’t end there. It turned out that Paula Brooks, an alleged lesbian blogger who had helped the alleged Amina with her blogging, was actually Bill Graber, a male retired construction worker in Ohio. It “was a major sock-puppet hoax crash into a major sock-puppet hoax,” Graber told me — and almost all of the hoaxing had been carried out online.

Last year, the Online News Association (ONA) acknowledged that online hoaxes were becoming a problem for journalists, organizing a whole session on how to weed out the true from the false on the Web. In the case of tweets, ONA suggested reporters go back to bootstraps reporting, by asking for a phone number from a Twitter account and calling the person to find out more.

A healthy dose of skepticism also helps. BlogPost considered writing about a couple of the fake world leader Twitter accounts by De Benedetti. But I felt that the notion that President Karzai would join Twitter right after a high-profile attack in Afghanistan seemed too convenient, and that President Assad’s use of the word “hoax” in his tweet seemed itself like it could be a hoax.

After the Gay Girl in Damascus hoax, Bell and I thought about the lessons we had learned. I read back over those lessons today, and all of them still apply — both to De Benedetti’s Twitter hoaxes, and to all online reporting.

The most relevant ones: Question anonymity with rigor. The seemingly impossible is often possible. Use old-school journalism tactics. Question why you’re focusing on a story. And always admit defeat.

The Guardian admitted it was wrong not only by retracting the fake Assad tweets it cited, but also by seeking out an interview with De Benedetti. “This American Life” host and producer Ira Glass similarly proved his commitment to being transparent about where his show erred when he interviewed a monologuist who had lied on his program — for a full hour.

As reporters, and as readers, hoaxes remind us to be suspicious of everything we see online, and to trust those suspicions. Just this week, filmmaker Spike Lee retweeted an address supposedly belonging to George Zimmerman, a Florida man who has sparked national outrage after shooting unarmed black teenager Trayvon Martin. The address Lee tweeted was wrong, and his mistake had very real repercussions.

To prevent these mistakes, reporters (and others) must be transparent about what they know and what they don’t. It’s the only way we can strengthen the weaknesses De Benedetti was so keen to expose.