A troll. Matt Chan/Flickr (CC) Vijaya Gadde, Twitter's top lawyer, has admitted that the company has been "inexcusably slow" in fighting off the kind of vicious online abuse we saw in the Gamergate scandal, in which video game fans send rape and death threats to women who suggested that some games featured sexist portrayals of women.

On the same day, a study of 134,000 abusive social media mentions showed that 88% of them occur on Twitter. Only a tiny fraction of online abuse happens on Facebook or other social media.

Online abuse — trolls, basically — are mostly a Twitter problem, in other words.

Trolls just don't have that presence elsewhere.

In an opinion article for the Washington Post, Gadde said Twitter was tripling the staff it devotes to chasing down abusive trolls on the service.

Gadde's article is a huge breath of fresh air for those of us who live and work on Twitter (and those who own TWTR stock, like me). It has been obvious for years — at least anecdotally — that trolls on Twitter are retarding user growth of the app. Twitter's user growth has been largely stalled under 300 million for months. CEO Dick Costolo has admitted that the atmosphere on Twitter is so poisonous that it drives users away. "We lose core user after core user by not addressing simple trolling issues that they face every day," he said in February.

Sue Perkins, the British TV host, gave up using Twitter last week after she received death threats merely because other people had suggested she might make a good replacement for Jeremy Clarkson on Top Gear. This ritual — a famous person announcing they're leaving Twitter after receiving death threats — is an almost weekly occurrence.

And it just doesn't happen on Facebook. Or at least, statistically, not nearly to the same extent. Here are the numbers from Kick It Out's study of abusive social media mentions from football fans. The organization looked at 134,000 mentions and found that 88% of abuse occurs on Twitter. We saw this first in The Guardian :

In other words, 88% of trolls are on Twitter.

You can see the rest of Kick It Out's data here.

To be a famous person on Twitter — to be someone with a large following, in other words — sounds like a nightmare, according to The Guardian:

Mario Balotelli, of Liverpool, was sent more than 8,000 discriminatory posts on social media, of which more than half were racist. Danny Welbeck, who moved from Manchester United to Arsenal in September, received 1,700 abusive posts, exactly half involving racism. Daniel Sturridge was sent about 1,600 discriminatory posts, more than 60% abusing him on the grounds of sexual orientation.

Some of Twitter's most "important" users are in fact trolls, such as "Old Holborn," an anonymous account published by a person who has devoted his (or her) life to abusing people from Liverpool.

Why does Twitter have this problem, but Facebook and LinkedIn and Instagram do not?

The answer is "real identity." On all those other platforms, the people in your network know who you are. You'd be an idiot to use racist language on LinkedIn, where employers can see your CV. And on Facebook, your family can see whether you're a jerk or not. So there is built-in behaviour moderation.

Not so on Twitter, where anyone can sign up with an anonymous email address and a fake name. Hopefully, Twitter's Gadde can do something that will bring about some identity transparency on Twitter. Here is what she said yesterday:

Even when we have recognised that harassment is taking place, our response times have been inexcusably slow and the substance of our responses too meager.

This is, to put it mildly, not good enough.

... We have seen this type of behaviour time and time again, including during GamerGate and other incidents involving both public figures and other individuals, so we are changing our approach to this problem, ...

Let us hope she succeeds.

Disclosure: The author owns Twitter stock.