Prosecutors requested jail and financial penalties for whistleblowers and a journalist who helped reveal industrial-scale tax avoidance schemes in the heart of Europe, as the widely-watched trial that follows the so-called LuxLeaks investigation ended on May 10.

Prosecutors requested 18-months in prison for two French whistleblowers, Raphaël Halet and Antoine Deltour, former employees of the audit firm PricewaterhouseCoopers (PwC).

State prosecutor David Lentz, who acknowledged that the LuxLeaks revelations unveiled “certain dubious practices,” also requested an unspecified fine against French journalist Edouard Perrin, who first revealed the documents.

Perrin, whose ground-breaking work was later expanded through a global investigation by ICIJ, revealed how the tiny nation of Luxembourg had effectively become a tax haven, slashing tax bills by billions of dollars for multinational corporations through secret tax agreements. Companies to have benefited from the shadowy deals included IKEA, Disney and Skype.

The LuxLeaks investigation was cited in an official European Commission report as paving the way for a “fundamental change” in Europe’s tax rules that requires member states to share details of tax agreements made with international corporations. Luxembourg’s own finance minister described the investigation as a “game changer.”

During the hearing, Deltour, who first leaked the documents before Halet followed, told the court, “I feel a certain pride in having contributed to these important advances to taxation in Europe.”

A lawyer representing investigative journalist and ICIJ member, Perrin, said, “my client has done only done one thing – reveal the truth”, he said. “To condemn him would be immoral and contrary to our rights.”

The court’s decision is expected in June.

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