The trial of International art dealer Guy Wildenstein on charges of tax fraud and money laundering began Monday in Paris. Wildenstein, 70, the Franco-American heir of a New York art-dealing empire, is accused of hiding the bulk of his inherited fortune in offshore accounts.

Wildenstein’s late stepmother Sylvia, and his sister-in-law Liouba, turned him in. The French authorities demand $600 million in back taxes, and he could face as much as 10 years in prison.