Andrés Sepúlveda sleeps behind bombproof doors in a maximum-security prison in central Bogota, Colombia. When travelling to judicial hearings or to meet prosecutors, he is accompanied by a caravan of armed guards with serious firepower. As they move at high speed through the capital, the motorcade uses sophisticated equipment to jam mobile phones to lower the risk of a coordinated assassination attempt.

Sepúlveda is one of the world’s most notorious election-rigging specialists. Now that he has been caught and put in jail, he is helping atone for his crimes by explaining how he fixed elections — and the people he used to work with want him dead.

But Sepúlveda isn’t the only specialist in this field. The tools he was using are deployed around the world. They’re costly, sometimes scandalous, but often legal. The disruption of democracy has become a great global game, and it’s one that British companies are playing too.

The recent Cambridge Analytica scandal raised an obvious question: did its role in mining Facebook data help send Donald Trump to the White House? But there is another angle that is just as important: what did Alexander Nix, its (now suspended) chief executive, mean when he said that his company is ‘used to operating through different vehicles, in the shadows’? That question was buried under the deluge of headlines about Facebook. This is a shame because it appears that there is an even bigger scandal than data-mining waiting to be exposed.

We’re academics, not investigative journalists. But between the two of us, we have crisscrossed the globe from Thailand to Tunisia, from Belarus to Zimbabwe, learning the tricks of the election-rigging trade. We’ve interviewed more than 500 top figures, from prime ministers and presidents downwards.

We have seen first-hand how digital tools can help complete a dictator’s toolbox of tricks. And we’ve put everything we’ve learned into a forthcoming book, How to Rig an Election, which might sound like a joke. But for those living in these countries, it could not be more serious.

You might think that elections weaken autocrats. Think again. Elections can actually help despots shore up their grip on power. Holding flawed polls can enable embattled governments to secure access to valuable economic resources like foreign aid, while reinvigorating the ruling party and — in many cases — dividing the opposition. Consequently, a number of authoritarian regimes that appeared to be in their death throes have used the ballot box to re-establish their political dominance.

The facade of democracy is being turned into a tool of oppression because an increasing number of leaders have worked out how to rig an election — or hire someone to do it for them. In many parts of the world, election rigging is now not the exception but the norm. It’s a multi-billion-dollar industry in which government contracts flow to those who deliver the ‘right’ result. In Kenya, Cambridge Analytica is said to have been paid $6 million to support the campaign of President Uhuru Kenyatta. There are many more such contracts, and many more companies in pursuit of them, constantly coming up with innovative ways to subvert democracy, from spreading fake news about opponents to adopting new technologies. The digital age has, alas, multiplied the potential for dirty tricks.

Take Azerbaijan’s 2013 elections, when President Ilham Aliyev sought to boost his democratic credentials by launching an iPhone app that enabled citizens to keep up to speed with the vote tallies as ballot counting took place. Touting its commitment to transparency, the regime said that the new technology would allow anyone to watch the results in real time. But those who were keen to try out the new technology were surprised to find that the results were posted on the app the day before the polls opened. Technology was being used to fix the process, not make it more robust.

Sometimes, though, old-school tactics get the job done. In the 2004 Ukrainian presidential election, voters in opposition areas were given pens filled with disappearing ink. When officials went to count the ballots, they just found a bunch of blanks. In the 1998 mayoral election in St Petersburg, the authorities sought to neutralise a rising opposition figure named Oleg Sergeyev. To do this, they found a pensioner and a tram driver who were also named Oleg Sergeyev and stuck them both on the ballot next to the ‘real’ Oleg. Because no photographs appeared on the ballot papers, voters didn’t know which of the three to pick, so the vote got divided three ways, and all the Olegs lost.

The digital frontier has opened up new possibilities that the political consultants of the 1980s could have only dreamed of. Elections can now be manipulated from anywhere in the world, so long as you can get online. Take Sepúlveda, who was somewhat of a pioneer in the business of election hacking. In 2005, he began breaking into the files of opponents’ campaigns, stealing their databases of voters and donors, and even defacing websites with digital graffiti. Within a few years, he was charging $20,000 a month to hack smartphones, or send mass texts or emails laced with perfectly timed misinformation. He promoted right-wing candidates and knocked down their left-wing rivals from Mexico to Venezuela (and most places in-between). As he put it from prison: ‘When I realised that people believe what the internet says more than reality, I discovered that I had the power to make people believe almost anything.’ This is a discovery that western firms — with bigger budgets — have also made.

Cambridge Analytica is now the best-known company using these tactics. It promises to ‘use data to change audience behaviour’. In the electoral context, it does this by getting data about voters through online sites such as Facebook and using it to encourage its clients’ supporters to vote and their opponents to stay at home. Its platform is bespoke: it targets messages specific to each individual according to a sophisticated profile of their likely attitudes and beliefs based on their internet activity. Breaking rules to access personal data — as Cambridge Analytica is alleged to have done by Facebook — may lead to prosecutions. But the method itself is not illegal.

Such strategies aren’t magical: they can’t turn lifelong Democrats into Republicans overnight, nor could they turn a dedicated Remainer into a fervent Brexiteer after a few pitch-perfect Facebook ads. ‘Big data’ is scarce and the number of people online much lower in parts of Africa and Asia. But even then, companies like Cambridge Analytica can have a negative effect by advocating and implementing irresponsible campaigns in more traditional ways, such as spreading misinformation about opponents. Another British firm, Bell Pottinger, recently went out of business after it was revealed that some of those working for the company had advised allies of the former South African president Jacob Zuma to manipulate racial tensions in order to shore up their own support base.

When big data is available, its effect can be significant. For people who don’t typically tune into politics, and those who have not yet made up their minds, being suddenly bombarded with carefully tailored messages aimed at playing to their deepest desires and fears can be a powerful push into political action.

The greatest challenge to 21st–century democracy is that uninformed voters are being replaced by misinformed ones. Alexander Nix put it well, during that Channel 4 sting operation, when he said of propaganda that: ‘Things don’t necessarily need to be true, as long as they’re believed.’ Uninformed voters often stay home. Misinformed voters turn out — and they often want to blow up the system or see a political rival permanently excluded from power. This can lead to anti-establishment politics, as in the UK and US; and in less politically stable parts of the world, to political violence and the discrediting of democracy itself.

Through using these strategies, autocrats have learned a simple but sad truth: it is easier to stay in power by rigging elections than by not holding them at all. So often we hear it said that the number of democracies in the world is rising — and we imagine that must mean world government is improving. Perhaps we want to believe it, and a willingness to be fooled — or, at least, a reluctance to ask too many questions — is part of the problem. But it is now time to wake up. Many of those who rig elections are outfoxing both their own people and western observers. Sometimes that is because autocrats (or their advisers) are smart, flexible and stealthy. But let’s not forget that Cambridge Analytica was used by the supposed leader of the free world, Donald Trump, and even by the UK Ministry of Defence.

As a result, a lot of powerful people might not want to look too deeply into all of this. Even in the West, few governments consistently live up to their rhetorical commitment to promote democracy in reality. The imperative of striking arms or oil deals and staying in power is simply more compelling than dealing with the messy and murky reality of widespread election rigging.

This has to change — and pro-democracy governments must do more to turn the tide. Firms such as Cambridge Analytica need to be subject to tighter regulation and scrutiny, not just for what they do at home but also for what they do abroad. We must make foreign aid dependent on genuine democratic progress, not a box-ticking exercise. And we must end our own practices of regularly flouting rules like campaign spending limits.

Around the world, democracy is being hijacked. And unless the western democracies start to care, election quality will continue to decline. This threatens to undermine the very idea of democracy, turning these elections into an empty ritual that the government always wins. The Cambridge Analytica revelations are the tip of the iceberg. This isn’t about one company or a handful of elections, it is about a concerted attack on democracy by a powerful alliance of authoritarian leaders and multinational companies. It has gone unnoticed and unanswered for too long. A parliamentary inquiry into what such companies are doing around the world would reveal, fairly quickly, how much has gone wrong. And why, for those who care about democracy, it is time to fight back.