Carlos Ghosn, formerly Renault CEO and chairman of Nissan, was arrested in November 2018 and charged with falsifying financial statements. He has denied any wrongdoing.
Mazars is probing Ghosn’s pay at Renault, and are looking into possible wrongdoing at RNBV, the Renault-Nissan joint venture registered in the Netherlands.
The FT reports that three private jets have been found at RNBV’s Dutch holding company, in addition to the sole plane that investigators previously knew of.
Ghosn is known for a busy travel schedule, often taking private flights for business. However, reports suggest that Mazars will investigate around €4.8m (£4.12m) worth of what it suspects were personal trips on corporate jets made by Ghosn and his family in a three-year period.
Auditors are also likely to question Ghosn over €12m (£10.3m) worth of company spending on entertainment and high-end clothing.
Among other expenses, Ghosn’s legal team will be asked to defend a €635,000 (£545,000) banquet at the Palace of Versailles, which took place on Ghosn’s 60th birthday.
In a video release, Ghosn insisted he was innocent, saying “I am innocent of all the accusations that came around these charges, that are all biased, taken out of context, twisted, in a way to paint a personage of greed, and a personage of dictatorship.
“This is a conspiracy … this is about a plot, about conspiracies, about backstabbing,” Ghosn added. He argues in the video that the allegations have come in an attempt to prevent a full merger between Renault and Nissan.
Mazars has been contacted for comment.