It began with a typed letter from a mysterious source instructing reporters to place a coded message in a French newspaper. Then, in August 2015, the source agreed to rendezvous with a journalist outside the Louvre in Paris and, later, at a suburban steak restaurant on the Mediterranean.
After this came the leak of hundreds of thousands of emails detailing a web of alleged corruption involving some of the biggest corporate players in the global oil industry. Next came police raids, denials of wrongdoing and a multimillion-dollar legal and public relations war waged by Monaco-based company Unaoil to undermine the allegations it had spent years paying bribes for corporate giants.
On Friday, UK corruption investigators laid the first criminal charges in the Unaoil scandal. The Serious Fraud Office charges against two former managers of Unaoil come 18 months after Fairfax Media exposed Unaoil's role as a facilitator running a global network of middlemen fronting for Western companies - including in Iraq for Australia's Leighton Holdings and in Kazakhstan for Worley Parsons. Unaoil's clients were seeking lucrative contracts in the Middle East, central Asia and Africa.
The fraud office also revealed on Friday that it had issued an extradition request for the Monaco-based Unaoil executive Saman Ahsani???, who, along with his brother Cyrus and father Ata, own and manage the firm.
The wealthy Ahsani family once socialised with European royalty and the business elite in the UK, Monaco and the Middle East. Cyrus was previously the treasurer of Monaco's Ambassador Club, led by royal Prince Albert. Now though, the socialising and charity soirees have stopped. The Ahsani men have been in lock down with defence lawyers and public relations specialists.
Unaoil was, according to the thousands of leaked emails, running an extensive network of shady middlemen who had connections to ministers and oil officials in Iraq, Libya, Iran, Nigeria, Kazakhstan, Syria, Azerbaijan, Malaysia and Algeria. The clients of Unaoil and its middlemen included household names such as Halliburton, Samsung, Hyundai and Rolls Royce.
The criminal charges are the latest in the slow-burn of developments in the Unaoil story and are illustrative of the global counter corruption and tax evasion regime the "five eyes" countries - US, UK, Australia, Canada and New Zealand - have sought to strengthen in the wake of the Unaoil, Panama Papers and, most recently, Paradise Papers scandals.
Investigators from the FBI, Australian Federal Police and UK Serious Fraud Office have spent months sifting through the leaked Unaoil emails and gaining co-operation from witnesses, including the confidential source who wrote to Fairfax Media in July 2015, sparking the scandal.
Recently, Canadian authorities launched an investigation into Unaoil's work for a North American firm. One of the men charged on Friday, British national Basil Al Jarah, set up shelf companies in New Zealand.
There are ongoing criminal investigations into several large UK listed companies, including the Wood Group and Petrofac, whose share price has plunged since the scandal broke. US engineering giant KBR as well as European oil industry firms ABB and SBM Offshore remain under investigation.
Earlier this year, Rolls Royce paid $US800 million ($1052 million) to settle Unaoil-related corruption inquiries in the US and UK. In a separate development, a former Unaoil employee admitted to bribing an official in the regime of Libyan dictator Muammar Gaddafi.
The criminal charges on Friday again put the spotlight on Australian's struggling corporate anti-corruption regime.
The two men charged with "conspiracy to make corrupt payments", Mr Al Jarah and his deputy Ziad Akle, are Unaoil's former Iraq managers. Mr Al Jarah, a former merchant seaman whose nickname was "the Captain", helped Leighton Holdings (now CIMIC) win $1 billion of oil pipeline contracts in Iraq in 2011 and 2012.
The criminal charges filed on Friday relate only to Mr Al Jarah's work assisting another oil pipeline contractor, Dutch firm SBM Offshore.
British authorities, relying on the Unaoil emails and backed by a superior anti-corporate bribery regime, have taken 18 months to lay the first Unaoil charges.
The AFP's six-year investigation into Leighton Holdings activities in Iraq, including its Unaoil dealings, has so far proved fruitless. A Senate inquiry is set to recommend reforms to Australia's anti-corporate corruption regime when it tables its report in December.
The leaked emails suggest that Unaoil, which was promised $75 million in commissions by Leighton to win work in southern Iraq, allegedly corrupted senior Iraqi officials to secure oil pipeline contracts.
Millions of dollars were funnelled by Unaoil to a Jordanian middleman codenamed "the doctor" and who allegedly corrupted Iraq oil minister Abdul-Kareem Luaibi??? and deputy prime minister Hussain al-Shahristani.
"We must not underestimate that doctor and his [group's] ??? ability to have the final say ... No matter how unpleasant we find it," states one Unaoil email in reference to efforts to secure Leighton an Iraqi pipeline contract.
After Fairfax Media exposed the Unaoil scandal in March 2016, the firm and its advisers issued denials, legal threats and alleged an unidentified person had attempted to extort Unaoil with what the company claimed was stolen data. Unaoil said it paid the extortionist, who threatened to release emails exposing alleged corruption to police or the media, $50,000.
In mid-2016, The Australian newspaper reported that "Unaoil is preparing to sue Fairfax Media for injurious falsehood and damages that could reach ... possibly hundreds of millions of dollars".
The paper's legal affairs editor Chris Merritt reported in February the lawsuit would be filed "within weeks" would cause "pain" for Fairfax Media. No lawsuit has ever been filed.
The Australian also published an exclusive interview with Saman Ahsani about the extortion, threatened legal action and what he said were unfounded bribery allegations that had cost hundreds of Unaoil staff their jobs.
"Forget about the Ahsani family, this has impacted the lives of many hundreds of hardworking Iraqis and expatriates," Mr Ahsani said.
On Friday, Fairfax Media unsuccessfully sought comment from Mr Ahsani about the efforts to extradite him to face bribery related charges. An overseas law enforcement source said further criminal charges are imminent. The AFP's inquiry into Leighton's Iraq dealings continues.
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