In 2015, James Bartholomew introduced an inverted and sarcastic usage of the term, referring to the common practice of paying lip service to a (supposedly virtuous) moral or political position, or expressing 'faux outrage' at something or other, and this usage was quickly picked up by other journalists. Of course this phenomenon has existed for centuries, but social media provides new channels for expressing and amplifying superficially held opinions.
Given this usage of the term virtue signalling, it was probably inevitable that people would also start talking about vice signalling, to refer to people saying outrageous things purely for effect.
For example, @PaulGoodmanCH accuses Arron Banks of vice signalling when he mounts an unfounded attack on Brendan Cox, the widower of the murdered MP Jo Cox. According to Goodman, Banks doesn't even believe what he is saying, he is merely saying it to gain more followers.
Again, there is nothing new about being deliberately outrageous in order to court controversy. In recent years, the tactic has been used with great effect by far right and alt-right politicians and entertainers, who strut around going "look at me, being dreadfully politically incorrect, aren't I awful?".
And there is a natural complementarity between the popular notion of virtue signalling and this notion of vice signalling - thus @sam_kriss defends viciousness and polemic in a good cause.
The vice signallers draw much of their energy from the knee-jerk disapproval of the virtue signallers. The political power of vice signalling is demonstrated by the extraordinary amount of broadcast airtime that is given to people like Nigel Farage, and (of course) the election of Donald Trump to the Presidency of the United States.
But vice signalling is essentially an opposition tactic. So what happens when the vice signallers gain power? @BDSixsmith imagines a dialectic process of vice being translated into virtue.
"That which seemed transgressive must appear conscientious. This is challenging for revolutionary movements if their identities were based on being oppositional, and helps to explain the internecine conflicts that tear them apart. If one’s ambitions transcend nihilistic mischief-making one must have beliefs because one thinks them principled, not merely as other people think them perverted."Perhaps thinking along similar lines, many people expected Mr Trump's style to change when he reached the White House. But @PeterBeinart argues that the president’s personal attacks are not a distraction from his policy goals, they are his policy goals.
The problem is that virtue signalling, in the sense popularized by Bartholomew, is also an opposition tactic. In his excellent piece on making Twitter safe for politics, @mrianleslie warns us to beware what he calls the "moral surge", the pleasure of asserting one's moral integrity in public. Virtue signallers can safely deplore the grubby compromises of practical politics, confident they will never be called upon to make any decisions with real consequences. They were the ones who refused to vote for Clinton because she wasn't virtuous enough. And look what they got instead.
James Bartholomew, The awful rise of 'virtue signalling' (Spectator, 18 April 2015)
I invented 'virtue signalling'. Now it's taking over the world (Spectator, 10 October 2015)
Peter Beinart, Trump's Grudges Are His Agenda (The Atlantic, 30 June 2017)
Paul Goodman, Vice Signalling (Conservative Home, 22 December 2016)
Ian Leslie, Unfight Club (Medium, 14 July 2017)
Ben Sixsmith, What is Vice Signalling? (14 April 2016)
Wikipedia: Virtue Signalling
updated 15 July 2017