Formula 1 is waiting to hear from the FIA about whether or not it believes Mercedes broke the sport's rules in testing a 2013 car at Barcelona after the Spanish Grand Prix.
If it decides the team has a case to answer, then the matter will be taken to the International Tribunal. This could be the first time that the IT has been involved in such a high-profile matter. F1's previous controversies, like the McLaren spy case in 2007, were ruled on by the FIA's own World Motor Sport Council.
Here, we'll explain exactly what the IT is, how it works and what it could do.
WHO SITS ON THE INTERNATIONAL TRIBUNAL?
The International Tribunal was set up in 2010 by the FIA General Assembly as part of a new judicial system. Its purpose is to rule on matters that cannot be immediately dealt with by race stewards.
The FIA statutes state: "The IT hears cases that have been submitted to it. It applies and interprets the present Rules with the aim of enforcing the Statutes and Regulations of the FIA, including the International Sporting Code."
The current president of the IT is Briton Edwin Glasgow, with the vice president Laurent Anselmi coming from Monaco. One of the key elements of the IT – a 12-man panel – is that it is completely separate from the governing body. In the FIA statutes, it is stated: "The IT operates totally independently from the other bodies of the FIA and the members of the FIA."
HOW WOULD A TRIBUNAL HEARING WORK?
If it is decided that Mercedes has a case to answer, then a judging panel of the IT will be convened.
According to the FIA statutes, the president will appoint a panel made up of at least three members, one of whom will be designated "President of the Hearing." To ensure independence, no members of the judging panel will be allowed to be the same nationality as one of the main parties of the case.
Both defense and other interested parties will be asked to submit written evidence before the hearing and the final proceedings will be open to the media – unless there are exceptional circumstances.
WHEN WILL THE TRIBUNAL MEET?
Should the FIA decide that an IT hearing is required, then there is a strict process that has to be followed. According to the FIA statutes, the prosecuted party will be given at least 15 days to submit their observations on the charges; and the prosecuting body will be given a further 15 days to reply. There will then be a further 15 days between the reply by the prosecuting body and the hearing taking place.
That 45-day window means in theory that even if a hearing is given the go-ahead this week, it could take until after the German Grand Prix in July for it to be scheduled. However, there are allowances – especially relating to sporting matters – which mean the process can be fast-tracked.
The statutes state: "The President of the Hearing may at any time decide to reduce or extend the time limits of proceedings."
WHAT WILL THE TRIBUNAL BE LOOKING AT?
One of Mercedes' explanations for running a 2013 car at the Barcelona test was that it received notification from the FIA that it would be OK to do so. Yet the FIA has stated that such approval was conditional on the Pirelli test opportunity being available to other teams.
Such intricate elements of the case may not matter to the IT, however, for its role is to simply decide whether or not there has been a breach of the regulations.
Mercedes' rivals are adamant that the team running its 2013 car in testing at Barcelona was breaking the rules, irrespective of any separate agreement that existed with Pirelli.
The IT statutes make it clear: "Unless stated otherwise, offenses or infringements are punishable, whether they were committed intentionally or negligently."
WHAT PUNISHMENTS CAN IT HAND OUT?
If the IT decides that there has been a breach of the rules, then the judging panel will hand out whatever punishment it thinks is appropriate. Although there have been some suggestions that one sensible solution to ensure parity for the teams would be to allow Mercedes' rivals a similar three-day Pirelli test, such an option does not appear possible under the FIA statutes.
The IT's punishments are limited to fines, bans or the alternative sanctions laid out in the International Sporting Code. The ISC says available sanctions are listed in the order of severity: reprimand, fines, obligation to accomplish some work of public interest, time penalty, exclusion, suspension or disqualification.
The FIA also states: "For the FIA Formula 1 World Championship and the FIA World Rally Championship, a penalty consisting of the withdrawal of points over the whole of the championship may be imposed.
"The International Tribunal may also impose directly bans on taking part or exercising a role, directly or indirectly, in events, meetings or championships organized directly or indirectly on behalf of or by the FIA, or subject to the regulations and decisions of the FIA."