On 30 November 2010 the arbitrator Heiner Geißler announced his ruling on Stuttgart 21, the planned underground main station. One of its conditions was a Stresstest. Deutsche Bahn had to prove that the new station could handle a timetable with 30 percent more capacity in the peak hour, with good operating quality. The railway ran the test, and the Swiss firm SMA und Partner audited it. On 29 July 2011 the results were presented and discussed in public, again with Geißler as moderator. The auditors found that the required 49 arrivals in the busiest hour could be handled. Opponents argued that the railway had not kept to its own rules. One group of critics said that the station could handle only 32 to 38 trains in the peak hour.