Five years ago, Rui Pinto was no different from any other football fan who longed to pull back the curtain that separates supporters from the inner workings of the sport. 

Curiosity eventually got the better of him and for three years between 2015 and 2018, the Portuguese man accessed millions of confidential documents, which exposed alleged corruption in football, and posted them on his website, Football Leaks.

But now it's Pinto who faces legal action. On Friday his trial began in Lisbon, at which he is facing 90 criminal charges including computer fraud, attempted extortion and violating privacy of correspondence, and a potential 30-year jail sentence.

Pinto claims his work was justified as it helped to expose illegalities within the sport and his defence team will call upon 45 witnesses to fight the charges, including U.S. whistleblower Edward Snowden, who could appear via video link from Russia.

Who is Rui Pinto?

In 2015, while still a student at a Hungarian University, Pinto created the website Football Leaks but opted not to reveal his true identity, instead using the pseudonym John. 

A year later, Pinto handed over 1.9 terabytes of data to German newspaper Der Spiegel and at least a further two terabytes in the two years that followed to the same publication. 

The documents exposed tax avoidance by some of the game's top players, extortionate fees paid to agents, match-fixing, ethnic profiling and a rape allegation made against Juventus star Cristiano Ronaldo. The former Real Madrid and Manchester United star wasn't charged after a Las Vegas court ruled that the allegation couldn't be proved beyond reasonable doubt.

Pinto's work prompted the writing of hundreds of articles on football's murky underworld and the opening of judicial investigations in France, Spain, Switzerland and Belgium.  

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Why was he arrested?

In 2019, Pinto's true identity was exposed and he was arrested by Hungarian police. Portuguese authorities asked for him to be extradited so he could face criminal proceedings, but his defence team argued that he was a whistleblower and entitled to protection under European law.

In March, Hungarian courts ruled that Pinto would be sent back to his homeland to face criminal charges, despite his persistent claims that much of the confidential data he accessed was shared with him by anonymous sources, rather than the result of hacking on his behalf.

Pinto has spent the months that have followed behind bars, sparking outrage among football fans across Europe, who have celebrated his work and held aloft banners calling for him to be released at games across the continent.