It was an unsettling week for tax-dodging tycoons and kleptocrats. Last Monday saw the online release of data from the Panama Papers. On Thursday, a global summit in London aimed at the offshore havens enjoyed by the super-rich.
For those who probe the opaque world of offshore finance, we could be witnessing a fulcrum moment where whistle-blowers' revelations have angered the world's long-suffering taxpayers enough to spur politicians into action.
Or, this is merely a hiccup, and a global network of lawyers and accountants will return to squirrelling away the wealth of Western businessmen and African despots in lax jurisdictions, from the Cayman Islands to the US state of Delaware.
"The jury is out over whether there is a real, substantial change of political will," James Henry, an economist and author who started chasing shady cash trails through Central America in the 1970s, told Al Jazeera.
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"The real scandal is not that this has happens, we've had expose after expose for 40 years. Governments have known what to do about it and just haven't, reflecting the political influence of the big banks and the lack of interest in doing anything about the kleptocrats."
The International Consortium of Investigative Journalists ( ICIJ ), a donation-funded group of reporters, released an online searchable database last Monday of some 200,000 offshore entities in 21 tax havens involving people from across the globe.
The data originates in some 11.5 million files belonging to Panama-based law firm Mossack Fonseca from the past 40 years that were leaked by a source known only as "John Doe" to a German newspaper more than a year ago, and then shared by the ICIJ.
The 2.6 terabytes of data in the Panama Papers revealed the hidden assets of politicians, officials, leaders, athletes and celebrities.
Iceland's Prime Minister Sigmundur Gunnlaugsson resigned amid street protests after his dealings were exposed.
Others in the spotlight include UK Prime Minister David Cameron, Presidents Vladimir Putin of Russia, Petro Poroshenko of Ukraine, and Mauricio Macri of Argentina - along with Argentinian footballer Lionel Messi and the Spanish film director Pedro Almodovar.
Offshore companies are not illegal, but they are often used to conceal both the origin and the owners of money, and dodge tax bills. Mossack Fonseca said it had been hacked, denied wrongdoing and took legal steps to halt further ICIJ revelations.
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The database released last week makes it possible for anybody with an internet connection - from prosecutors to journalists and members of the public - to comb through a stripped-down version of the data.
Unlike WikiLeaks, which posts all leaked documents online, the ICIJ has not carried out a wholesale "data dump" and has withheld emails, invoices, passports, telephone numbers, and other personal information.
Instead, ICIJ online editor Hamish Boland-Rudder described "information that, in more transparent jurisdictions, you might expect to see on a corporate register - shareholders, addresses, directors, clients, intermediaries and so on".
He predicted fresh scandals as more suspect cash trails are spotted.
"The Panama Papers have shed light on an extremely secretive world that is sometimes used to do really bad things," Boland-Rudder told Al Jazeera.
With the release comes a push for more openness and regulation.
Some 300 economists signed a letter urging leaders to end tax havens, saying they only benefited the rich and multinational firm, boosting inequality and costing poor countries some $170bn in lost taxes annually.
"There's no economic justification for trillions and trillions of dollars to be held offshore, facilitated by banks and financial institutions. It drives inequality and reduces economic growth," Judy Beals, Oxfam America's private sector expert, told Al Jazeera.
"Now, the question is: what will world leaders do about it?"
US President Barack Obama recently used executive powers to unveil limited curbs on tax evasion and called on Congress to pass more detailed measures down the line. Prosecutors in the US, Canada and elsewhere are scouring the Panama Papers for crooks.
On Thursday, Cameron hosted some 40 world leaders, campaigners, and officials from the World Bank and other institutions in London for an anti-corruption summit to tackle a "taboo" subject "head on", the prime minister said.
Action by Washington and London is welcomed. Both governments oversee some of the world's most notable tax havens, from the US states of Nevada and Delaware to the Cayman Islands, Jersey and the British Virgin Islands.
According to John Christensen, director of the Tax Justice Network , a research group, Cameron must demand public registries naming the owners of offshore firms sheltered in British overseas territories and Crown dependencies.
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The same goes for offshore trusts, which are another "sophisticated weapon of concealment", he added.
"If Cameron doesn't include offshore trusts, then he leaves a gigantic gap through which we can expect all the crooks of the world to rush as quickly as possible to escape from disclosure of funds," Christensen told Al Jazeera.
"If they're not, then I'm afraid we will have to record the corruption summit as a failure."
As well as facing resistance from back-bench politicians and city financiers, Henry, author of a forthcoming book The Pirate Bankers, posited other reasons for Western leaders to talk tough, but ultimately yield on tax havens.
According to Henry's data, offshore tax havens store some $12.1 trillion that has exited the world's 139 poorest countries since the 1970s. Instead of building schools in rural Africa, that cash pours into such safe-bet investments as US Treasury bonds.
"The developing world as a whole is a net lender to the rich countries," Henry said. "The wealth that's missing … has gone somewhere and is paving the streets of Zurich, the City of London, and New York with gold."
He suggested a 1 percent "kleptocrat tax" on anonymous wealth, which could raise as much as $100bn annually and prove handy in tackling mankind's woes - from climate change to refugee misery and lethal diseases.
While they are muted, there are also supporters of tax havens.
Nuri Katz, founder of Apex Capital Partners, a Caribbean-based finance advisory, said that while all wealth should be declared, low-tax zones can spur economic growth .
He cited the world's many "moms and pops" with pension investments in Apple, Google and other firms that boost their stock value and cut costs by conducting business in low-tax areas.
"There are legitimate ways that jurisdictions with different tax bases assist legitimate business to work," Katz, speaking from Antigua, told Al Jazeera.
"You should not be able to hide your money from tax authorities, but you should be allowed to legally use various jurisdictions around the world to manage your tax exposure, including Ireland, the UK, New Zealand and so on."
Follow James Reinl on Twitter: @jamesreinl
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Source: Al Jazeera