Hamilton along with Jenson Button and Takuma Sato used more than the regulation number of wet weather tyres practice on Friday morning at the Autodromo Jose Carlos Pace.
The McLaren team admitted a mistake had been made. FIA technical delegate Jo Bauer noticed the error and reported it to the race stewards.
The three are believed to have broken article 25.3 of the Sporting Regulations which states:
During the Event no driver may use more than fourteen sets of dry-weather tyres, four sets of wet-weather tyres and three sets of extreme-weather tyres.
No driver may use more than two sets of each specification of dry-weather tyre during P1 and P2.
No driver may use more than one set of wet and one set of extreme-weather tyres during P1 and P2.
A set of tyres will be deemed to comprise two front and two rear tyres all of which must be of the same specification.
Potential punishments are covered by article 31.6:
In the event of a driving infringement during any practice session the Stewards may drop the driver such number of grid positions as they consider appropriate. Unless it is completely clear that a driver committed a driving infringement any such incident will normally be investigated after the relevant session, any penalty imposed shall not be subject to appeal.
It is not clear what punishment, if any, the three may face. Ferrari started both its drivers on wet weather tyres against the instructions of the race stewards at the Japanese Grand Prix and were unpunished after the drivers were ordered to change tyres.
But they broke a stewards’ ruling rather than a specific regulation, and the team claimed not to haver received the e-mail informing them of the decision.
It is also worth noting that in 2002 the stewards at the same race granted a special dispensation to Ferrari allowing Michael Schumacher to have access to a larger number of tyres than usual, as he and team mate Rubens Barrichello were using different models of Ferraris with different wheel mounts.
But’s it’s unlikely the stewards will give much leniency to what appears to be a straight breach of the rules, regardless of whether any advantage was gained by the drivers.