With the tribunal hearing for Mercedes and Pirelli set to happen in 7 days time, evidence is building up against the Mercedes F1 Team, as a leaked gentlemen's agreement now also seems to have been breached.
Germany's SportBild has published a document that seals a gentlemen's agreement between all current F1 teams. The document states that if any team wanted to run development testing for 2014, any test would have to be jointly approved by the testing committee - the teams - and the FIA.
Although Ross Brawn denied at Canada the test was actually "secret" but rather "private", the agreement requires any team that is out to test elements for 2014 is bound to inform all other competitors beforehand. This not obviously didn't happen, as Red Bull Racing for one heard from the press at Monaco that a test had taken place.
Furthermore, Pirelli have said that the testing was aimed to develop 2014 tyres and had nothing to do with resolving the safety issues that appear to be going on with the current set of 2013 tyres.
The problem essentially is that it is Mercedes team principal Ross Brawn who signed the agreement, while he also clearly stated that it was him who approved the Pirelli test with the Mercedes AMG F1W4 at Barcelona. And even though the agreement is not enforceable in court, it severely undermines the position of Ross Brawn, and Mercedes as a trustworthy competitor in Formula One.