The author of a book about public shaming on social media says today's response to Border Force's plans to check people's visas on the streets of Melbourne shows how Twitter and other platforms can also be used to positive ends.

Jon Ronson's book So You've Been Publicly Shamed is about how social media can become an instrument of control and how public shaming on forums like Twitter can have a devastating effect on people's lives.

While the book focuses on the dark side of social media, Ronson told 7.30 the rapidly mobilised public outrage over the Border Force operation showed the other sign of the coin.

"What happened today in Victoria today proves that we have the power now," he said.

"We like to see ourselves as powerless, punching up - but actually we have the power now. And it's incumbent on us to use our power judiciously, because nobody is going to tell us what's a serious transgression and what's an un-serious transgression.

"So a government doing a social policy is being treated with the same level of derision as somebody who tells a joke that comes out badly."

But Ronson also warns that not everything will be rosy in the "tech-utopian" garden.

'Social media is turning us more psychopathic'

He cited the case of New York publicist Justine Sacco who, as she was about to board a plane for Africa, tweeted: "Going to Africa. Hope I don't get AIDS. Just kidding, I'm white!"

Sacco switched her phone off for the flight and by the time she landed in Johannesburg the hashtag #hasjustinelandedyet was trending worldwide. More than 100,000 people had commented on her tweet and she had become the target of an angry internet mob.

Jon Ronson believes that like most people who are targeted, Justine Sacco was perceived to have 'misused her privilege'. But he said the vociferous response to her comment was about more than just a misinterpreted joke.

"I think it's gone from a place of curiosity and empathy to a place of cold, hard, instant judgement, on the scantest of evidence," he said.

"Twitter's like a sort of mutual approval machine, we surround ourselves with people who feel the same way that we do and we approve each other.

"Tech-utopians call this a new type of democracy, but it isn't. It's the opposite of democracy.

"In democracy you listen to each other.

"Social media is turning us more psychopathic ... it's robbing us of our empathy."

Ronson tweeted in support of Justine Sacco and became a target himself, but he believed it was the only way to respond.

"The way to redress the balance is, if you see an unfair or ambiguous shaming, is to speak up, to say something about it," he said.

Ronson, who is in Australia for the Melbourne Writers Festival, wrote about the incident in So You've Been Publicly Shamed.

"I wrote a book that was critical of the constant waves of public shaming on social media and as a result, my book was publicly shamed on social media," he said.

"So, for a while I got off Twitter and it was great.

"I read a book and I met people in real life who I hadn't seen in ages and I felt so happy.

"Being off social media made me feel so happy and then within a couple weeks, like a pitiable junkie, I went back onto social media where I'm miserable again."