“What people mean to show,” says Higgins, “is not all they are revealing.”

We are Bellingcat is Higgins’ plain-spoken account of his own discovery of the wealth of information freely available online, and where that discovery took him.

In 2011, he was indulging an interest in the Arab spring, sharing social media discoveries from Libya with a Guardian newspaper blog. But when a video supposedly showed rebels to be in Brega, a port and oil storage facility claimed by Gaddafi loyalists, this was loudly denounced as disinformation. The video could have been from anywhere.

So Higgins sat down to watch and made a sketch map of glimpsed side turnings, then painstakingly searched satellite images until he found a Brega street layout that matched every junction and open area.

The rebels were indeed there, and not only had he proved it, but he could say in exactly which street.

“Seated in my office in Middle England, I had clarified the front line of a war zone thousands of miles away. All I had needed was a YouTube clip and Google Maps, aided by a sketch on printer paper.”

In 2014, several coups later, he founded Bellingcat, three days before the downing of flight MH17. This was to lead the fledgling organisation to global attention.

Its name is a reference to a fable attributed to Aesop, in which a group of mice decide to give themselves advance notice of a predatory cat by hanging a bell round its neck. But this is a task no mouse will actually attempt. His organisation’s mission, Higgins tells us, is to bell the cat.

“We battle the counterfactual forces warping society. We insist on evidence. And we show ordinary citizens how to expose wrongdoing and demand accountability from the powerful.”

The book is written with the same openness Bellingcat claims to bring to its research. It identifies evidence previously overlooked, verifies it, and amplifies the results by providing all its sources and leaving others to judge for themselves.

The difference between lies and BS? One is a ‘greater enemy of the truth’

Mocked by the Kremlin’s state-controlled broadcaster RT (formerly Russia Today) as an “unemployed internet addict” who “is part of a new generation of cyber armchair sleuths who use open-source social media to gather ‘intelligence’ from on the ground”, Higgins is happy to plead guilty on all counts.

“Open-source investigation is not about formal qualifications. Your reputation is your results.”

And these have been spectacular. The account of the process involved in showing that MH17 had, in fact, been shot down using a surface-to-air missile, that a Russian Buk missile battery had been used, and that a crew from Russia’s 53rd Brigade had carried out the operation, is reminiscent of the best moments of Sherlock Holmes. The information is all there to see: it just takes diligence to see it.

In China, the renrou sousuo or “human-flesh search engine” – millions of pairs of eyes – have long scanned online photos and social records. But this has typically been in the service of virtual vigilantism, which Bellingcat avoids.

“For instance, when reporting on the 53rd Brigade, we excluded the identification of the low-ranking Russian soldiers not linked directly to the downing of MH17,” says Higgins.

Proving Kremlin involvement in the Skripal poisoning by naming the perpetrators caused the biggest stir yet. How could a bunch of citizen investigators somehow out a Russian “hit team”?

Higgins’ answer is simple.

“Evidence exists and falsehoods exist, and people still care about the difference.”