The luxury cars are long gone, and the five-story mansion near the Champs Elysees is out of bounds for Teodorin Obiang. 

Equatorial Guinea's playboy vice president may still be living the high-life at home, but in France, he is a convicted criminal — thanks to a recent verdict that marks a stunning success for a scrappy French watchdog seeking economic and social change through the courts.

Read more: French court finds African playboy Teodorin Obiang guilty of embezzlement

"It's a new wind," says William Bourdon, founder of French nongovernmental group Sherpa and lawyer for Transparency International France, the two organizations spearheading the 'ill-gotten gains' case targeting Obiang and families of two other African leaders. "What was considered absolutely unrealistic 10 or 15 years ago is now considered possible."

Founded in 2001, Sherpa works with a shoestring staff that includes two full-time lawyers and nearly two dozen volunteers near the busy Saint Lazare train station in central Paris. The group is strapped enough so it had to scramble for funds to fly in witnesses for one of its cases — and to worry about the potential damage of defamation fines threatened by some of the transnational companies it goes after.

Getting creative

But limited means do not translate into limited ambitions — earning Sherpa powerful enemies as well as supporters. 

It has teamed up with other NGOs to file complaints against French banking giant BNP Paribas for alleged complicity in Rwanda's 1994 genocide and against Swiss-French cement company LafargeHolcim, which it accuses of financing terrorism in Syria. French judges are investigating both cases, which are considered a first of their kind in France.

Sherpa has also taken on French construction company Vinci SA, for allegedly using forced labor in buildings for Qatar's 2022 World Cup, and supermarket chain Auchan, on grounds it misled customers about working conditions linked to a deadly factory disaster in Bangladesh.

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"We have to be creative to find a legal basis" to link French multinationals to abuses allegedly committed thousands of kilometers away, says Sherpa's litigation head Marie-Laure Guislain. "The violations of human rights must also be really clear — like environmental damage or working conditions. And they must be very big, to affect communities as a whole."

Justice as a weapon

While some NGOs use 'name-and-shame' tactics against corrupt companies and wrongdoers, Sherpa's staff argue legal tools are more sustainable. 

"'Name and shame' works sometimes but not always," Guislain says. "What we have seen so far is they are really only willing to change their practices before justice." 

Sherpa began pursuing charges against Obiang a decade ago. Its argument: that the son of Equatorial Guinea's longtime president, Teodoro Obiang-Nguema, used public funds to pay for a lavish lifestyle here, including a Paris mansion and a fleet of luxury cars. Obiang's lawyer argued the property, equipped with gyms and a night club, served as the nation's diplomatic mission. 

In late October, French judges handed Obiang a three-year suspended sentence along with a suspended €30 million ($35 million) fine. He is appealing the verdict.

Families of two African heads of state — Republic of Congo President Denis Sassou-Nguesso and Gabon's deceased leader Omar Bongo — also face corruption investigations in 'ill-gotten-gains' cases.

Read more: 'Systemic corruption' in Africa, watchdog says

Observers say the Obiang sentencing reflects a broader sea change in France, long accused of turning a blind eye to lavish property snapped up by African dictators and their families — and for maintaining a tangle of shadowy business and political ties with former colonies, dubbed "France-Afrique." 

"Teodorin is somebody who seems to be completely immune to any sort of pressure," says Human Rights Watch researcher Sarah Saadoun. "Here is a case where France was able to pierce this impunity by seizing some of his assets. It's a tremendous victory in a context where it's very hard to have victories."

Read more: Fighting corruption in mining poses tough challenges

Also groundbreaking is new French due-diligence legislation that went into effect this year, forcing multinationals to address the impact of their actions on people and the planet. Criticized by France's Medef employers union and conservative politicians and hailed by anti-corruption groups, it is considered by some a model for other European countries.

Pay-off for 'Islamic State'?

Watchdogs like Sherpa are also powered by 2013 legislation granting them the status of injured parties for alleged corruption crimes. 

"It marks a huge change in French law," says Ken Hurwitz, senior legal anti-corruption officer for the New York-based Open Society Justice Initiative, one of Sherpa's funders. "Because it gives standing to civil-society organizations focused on anti-corruption to actually bring a civil party case." 

The legislation could help buttress Sherpa's arguments as it goes after powerful companies.

In the BNP case, Sherpa and two other groups claim the French bank knowingly approved a $1.3 million transfer that helped arm Hutu fighters during the 1994 genocide. BNP did not reply to an emailed request for comment. 

In June, judges also opened an inquiry into Swiss-French company LafargeHolcim, accused of making payments through middlemen to the "Islamic State" group to keep its Syria plant open. The move followed a suit filed by Sherpa, the European Center for Constitutional and Human Rights and 11 ex-Lafarge employees, who fled hours before IS ultimately attacked the factory in 2014. Last week French investigators issued preliminary charges against three Lafarge officials for financing a terrorist enterprise and endangering others.

Lafarge says an internal investigation found "significant' errors of judgement that violated the company's standards and has taken measures to correct them. It also acknowledged payments to third parties, but says it is unable to identify them. 

Sherpa is now raising money to fly Lafarge's former Syria employees France, even as others want to join the suit, says Sherpa litigation head Guislain. 

"These are really employees who have suffered traumas," she adds, describing some staff as having been kidnapped by IS and physically attacked. "And we can also define them as crimes against humanity."

Threats, intimidation and crying wolf

Not all Sherpa cases are gaining traction. Accusations of Liberian "war timber" purchases by French companies or corruption involving the family of ex-dictator Moammar Gadhafi are languishing for myriad reasons. 

Not surprisingly, the NGO has attracted its share of critics. Founder Bourdon — who represents whistleblower Edward Snowden and has taken on less savory clients such as former oil chief and convicted embezzler Loik Le Floch-Prigent — says he has faced numerous threats. Judges are looking into a reported menace to "eliminate" him, allegedly tied to a son of Congo-Brazzaville's Denis Sassou-Nguesso.

Read more: Freedom is acting without asking permission, Edward Snowden tells Berlin

Litigation head Guislain says companies are also launching defamation suits with mounting compensation claims as a way to silence Sherpa and other anti-corruption groups. 

"It's a whole strategy of intimidating NGOs," she says. "We're lucky that we're French lawyers, but our partners are terrified when they are attacked in French courts."

For their part, some critics argue Sherpa's attacks are easily and unfairly destroying the reputation of large and vulnerable companies for the sake of media attention and funds. 

"They file a complaint and their objective is met," says Jean-Pierre Versini-Campinchi, lawyer for French construction company Vinci, which sued Sherpa over its Qatar worker abuse claims.

Read more: Amnesty International calls on FIFA to do more to end labor abuse in Qatar

"The bigger the company, the bigger the media interest," he adds. "Sherpa knows that if there is abuse, it's not going to be found at Vinci, but in much smaller companies." 

The cases do resonate — and there is no lack of new causes to take on. Bourdon cites corrupt African leaders allegedly buying a "cynical silence" from the West in return for fighting terrorism, and dirty money hiding in opaque countries. 

At the same time, he describes a new, more socially responsible generation growing up in France and "enthusiasm" among African NGOs in adopting Sherpa's tactics. In March, Bourdon helped to launch an African whistleblowers' site, PLAAF, now operating in several countries.

"I think we are the demonstration that small is beautiful," he says.