Trudy Coughlan wasn’t to know. As far as she was concerned, Document Image Processing Systems, in Wal-ton-on-Thames, Surrey, was just another photocopying shop, staffed by anonymous sales assistants.

So when she walked through the door last June, clutching a sheaf of 780 pages, handed them over to the middle-aged man behind the counter and asked him to copy them onto two CDs, she had no reason to think anything more about it. She gave her name and left the shop, promising to return some time later to pick up the papers and CDs.

What Coughlan wasn’t to know was that the man was a keen follower of Formula One. If she had, she probably wouldn’t have given him the papers, because emblazoned across many of them was the prancing horse logo of the Ferrari F1 team. Not only that, but they contained information that was so sensitive no one outside the Italian company’s headquarters in Maranello should have been in possession of it; certainly no one in Surrey, home of the McLaren F1 team, arch rival to Ferrari, and at that very moment well on the way to winning the 2007 world championship.

None of this was lost on the shop assistant. Once Coughlan had left, he got to work. First he Googled her name and discovered that she had the same surname as Michael Coughlan – chief designer of McLaren’s F1 team. Then he Googled Ferrari and found the contact details of Stefano Domenicali, the company’s sporting director. Finally he sent an e-mail that would trigger one of the most serious feuds of F1’s 60-year history.

Today, a year later, as the drivers line up on the grid at Silverstone for this year’s British Grand Prix, the world of motor racing is hoping to put the disasters of last season behind it. However, the spying scandal has left an acrid whiff of deceit amid the smell of burning rubber and race fuel.

It is not hard to see why resentment still lingers between the teams. McLaren and Ferrari, the two biggest teams in the championship, fought a war of words in public; employees of both companies had their houses raided by lawyers or police, and the case is the subject of a civil suit brought by Ferrari against the Coughlans in the High Court, the details of which are confidential but are believed to refer to possessing stolen technical data.

The separate investigation by the Fédération Internationale de l’Automo-bile (FIA), F1’s governing body, resulted in a historic ruling against McLaren that cost the team the 2007 constructors’ championship as well as a record £50m fine. There was in addition the threat of more sanctions that would have see n the team banned from future races, effectively bankrupting the Woking-based company.

Understandably, neither the teams nor the FIA want to reopen old wounds; but much of the detail can now be pieced together. It is a story of greed, ambition and rivalry, and can be traced back to the sensitivities of one man who felt wronged – Nigel Stepney, Ferrari’s chief mechanic.

Stepney, who strongly denies allegations of wrongdoing, is the subject of a police investigation in Italy. However, according to court documents leaked to the Italian media as well as minutes from the FIA hearings, his role in the drama was pivotal.

Stepney’s resentment can be traced back to 2006 and the announcement that Michael Schumacher, the talismanic Ferrari driver, was to retire. The move precipitated a restructuring within the company that saw Ross Brawn, the technical director, who had led the rebuilding of the team from its sorry state a decade earlier, decide to take a sabbatical in 2007.

For Stepney this was mixed news. He was losing his mentor but might have been expected to gain in the inevitable reshuffle. He’d been Brawn’s right-hand man, the fixer who ensured Ross’s directions were followed. He was brilliant at his job. He prided himself on the calm British order he brought to a Latin operation. Behind that exterior, however, lay a surprisingly highly strung personality.

In the restructuring that followed, Stepney’s aspirations of becoming a technical director himself were dashed. Put in charge of team performance development, he felt sidelined. From Ferrari’s point of view, Stepney did not have the kind of formal engineering training often seen as a prerequisite for such a senior role; plus it liked to show it was capable of growing its own talent. Stepney, who had been brought in as a chief mechanic from Benetton in 1993, was still seen at Maranello as a highly-paid outsider, reportedly earning about $1m a year.

He talked openly about his dissatisfaction to the press and suggested he might look for employment elsewhere. In February 2007 he asked Ferrari to assign him to a post that did not involve travelling to races, and the management complied. Some time afterwards, Stepney sowed the seeds of the dispute by opening new lines of communication with Michael Coughlan, the chief designer at McLaren.

According to those who know them, both men are loud, old-school engineers steeped in F1 history, who have been involved in racing since their teens. They like a joke and a drink and worked well together as colleagues for Ferrari and Benetton in the 1990s, although they had been out of direct contact for some years. That changed between March and July 2007 when, according to Italian police, 288 texts and 35 calls appeared to have passed between the two men.

In late March, Coughlan – who later claimed to have become wary of the information – convened a meeting with Jonathan Neale, the McLaren managing director, and told him about his contact with Stepney. Alarmed, Neale instructed the IT department and Coughlan to block all e-mails from Stepney. The following month, Coughlan travelled out to Barcelona, ostensibly to ask his former colleague to stop communicating with him.

Exactly what was discussed isn’t known, but as Stepney drove him back to the airport, Coughlan claimed he handed over 780 pages of documents. “My engineering curiosity got the better of me and I foolishly took the documents,” Coughlan said in a witness statement, which was leaked to the Italian press.

Inside was every detail of the 2007 Ferrari’s design, operation and performance. It was virtually an x-ray of the car and team, with every mechanism laid out and explained, complete with schematic drawings and departmental budgets.

Back in Britain, Coughlan’s wife made her fateful trip to Document Image Processing Systems to copy the papers onto two discs. She then reportedly shredded the paper dossier, burning the remains in the back garden. On June 24, just after Trudy Coughlan had picked up her discs from the photocopy shop, Stefano Domenicali arrived at his office in Maranello and browsed through his inbox. The unusual e-mail from a shop in Surrey stood out. He read with growing amazement, slowly grasping its implications. If it was true, it meant not only that his whole operation was compromised, but also that the team’s greatest rival could potentially know almost as much about Ferrari’s car as he did.

Ferrari had a pretty good idea who might be responsible for passing top secret information to its rival. In May it had made a detailed complaint to police following an incident when white powder was found around the fuel tanks of one of the cars being prepared at the factory for the Monaco Grand Prix.

The tanks were emptied, the powder was analysed and found to be detergent, which if left in the tank could do serious damage to the car. Sabotage was suspected and there was apparently CCTV foot-age of Stepney acting suspiciously near the car. In response, Italian police searched Stepney’s home and found powder reportedly matching that around the car in Stepney’s pockets; he was suspended, pending an internal investigation. Stepney denies sabotage: “It’s all part of a dirty tricks campaign against me,” he was later reported as saying.

Ferrari acted quickly when it heard of the possibility of blueprints of its car being in the hands of a McLaren employee. It contacted a firm of English solicitors who applied to the High

Court. At 7.30am on July 3, solicitors acting for the court arrived at the Coughlans’ home, armed with a court order entitling them to search the premises. They found the two discs. The same day, McLaren suspended Coughlan and Ferrari announced it had fired Stepney.

The next day, July 4, the FIA launched an investigation into the affair, and summoned McLaren to a meeting of the body’s world council to face charges of fraudulent conduct.

The council found the team guilty of possession but imposed no penalty, as no evidence could be found that the material had leaked beyond Coughlan and into the McLaren organisation: Ferrari was outraged and issued a statement saying the verdict “legitimised dishonest behaviour in F1”.

However, the FIA reserved the right to recall McLaren if new evidence emerged that details of Ferrari’s technology had permeated deeper into the team – and made explicit the threat of exclusion from the championship for 2007 and 2008. That might have been the end of the story, had not the long-running rivalry was pretty upset,” said Dennis later.

“In the conversation that took place he said, ‘I have something on my e-mail system that is from one of the engineers’.” It was an admission that blew McLaren’s defence out of the water. It had contended that since no one apart from Coughlan – a “rogue employee” – knew about the stolen files, the team should not be punished collectively; now it seemed to go right to the heart of the organisation.

Dennis immediately contacted the FIA, but his worst fears were realised when, in the ensuing investigation, damning e-mail and text messages were uncovered. From a McLaren test driver to Coughlan on March 21, 2007, at 09.57: “Hi Mike, do you know the Red Car’s weight distribution? It would be important for us to know so we can try it in the simula-between McLaren’s two top drivers, Lewis Hamilton and Fernando Alonso, conspired to reignite the scandal.

Throughout the season, tempers and tensions had been hotting up between the two drivers. Alonso had never come to terms with his rookie teammate’s blistering start to the championship and was convinced that the British driver was being given preferential treatment by Ron Dennis, the McLaren boss. The simmering feud boiled over during the Hungarian Grand Prix in August 2007 when Alonso blocked Hamilton’s exit from the pits during qualifying.

Alonso later stormed into Dennis’s office where the Spaniard dropped a bombshell: he had personally known about sensitive information regarding the Ferrari car. “Fernando arrived and he tor.” The driver then sent the details of Coughlan’s reply to Alonso via e-mail, who replied: “Its weight distribution surprises me; I don’t know if it’s 100% reliable, but at least it draws attention.”

It wasn’t just technical details: “All the information from Ferrari is very reliable,” read another e-mail from the test driver to Alonso. “It comes from Nigel Stepney . . . he’s the same person who told us in Australia that Kimi [Raikko-nen] was stopping in lap 18.”

The driver communications were enough for the FIA: in September it stripped McLaren of its points in the constructors’ championship and levied its record £50m fine. Things went downhill from there on. In October, Hamilton had a disastrous final race and lost the drivers’ championship.

In November, it was announced that Alonso would leave the team. The following month, McLaren was forced into a humiliating apology to the FIA and a guarantee that no Ferrari intellectual property had been incorporated into its 2008 car. Meanwhile, Italian police are continuing with their criminal investigation of Stepney in relation to the sabotage claims.

For its part, the FIA issued a statement in March this year cautioning racing teams about dealing with Stepney: “the FIA recommends to its licensees that they do not professionally collabo-rate with Mr Stepney without conducting appropriate due diligence. . . This stands until July 1, 2009”.

As for Coughlan, both he and his wife are still the subject of High Court proceedings brought by Ferrari. The Sunday Times was unable to get in touch with them for comment.

Back in Walton-on-Thames, the pho-tocopy shop on a nondescript industrial estate was locked when we visited last week. Contacted by telephone, Gary Monteith, the shop’s owner, refused to confirm or deny that he was the man who contacted Ferrari about the documents.

“I don’t see why you think I played such a big part in what happened,” he said. Luca di Montezemolo, the boss of Ferrari, wasn’t so coy, dedicating his team’s grand prix win in Belgium to the copy-shop worker: “Without him it would never have been possible to shine the light onto one of the worst pages in the history of motor sport,” he said.

Additional reporting: Mark Hughes