Tilly remained defiant Tuesday despite the conviction, saying he is a British citizen and will take his case to the European Court of Justice.
"(The trial) has only just begun," Tilly declared.
His lawyer, meanwhile, said he was not aware that his client was a British citizen.
Picotin said he had hoped Tilly would get a longer sentence. "I'm sure that if he gets out he'll begin again," the lawyer said.
The case raised echoes of another controversial trial involving France's richest woman, 90-year-old L'Oreal heiress Liliane Bettencourt, who was swindled by a French tax lawyer into handing over to him a private Seychelles island.
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