Representatives of Red Bull, McLaren and Williams were at the FIA's Place de la Concorde headquarter
Jun.20 (GMM) Red Bull's Christian Horner made a surprise appearance in Paris on Thursday as the 'test-gate' hearing began.
But also at the FIA's Place de la Concorde headquarters were representatives of McLaren and Williams, as the governing body's lawyer clearly accused Mercedes of breaking the rules with its highly controversial Barcelona test last month.
"Any running on the track is deemed to be testing," the FIA's lawyer said.
"It is difficult to say that Mercedes gained no benefit," he added.
The FIA also alleged that Mercedes and Pirelli were "very odd" in how they went about seeking permission to test, having made "informal" calls and emails to Charlie Whiting and the governing body's legal department, but then going ahead with the test without obtaining clear answers.
Mercedes' lawyer hit back by arguing the Brackley based team did not actually break the rules, because the sporting regulations say only that a team may not 'undertake' a test.
"It is irrefutable it was a test undertaken by Pirelli," he said.
The Mercedes lawyer also accused Ferrari of doing more than 1000 kilometres of testing in the weeks before the Barcelona session, while admitting that having Lewis Hamilton and Nico Rosberg wear all-black helmets was a "regrettable" decision.
"We acknowledge this aspect was bound to raise suspicion," he acknowledged.
A bullish Pirelli, meanwhile, argued that it fully complied with its contract with the FIA, and insisted it cannot be punished because it is not a team or driver.