Controversy, Michael Schumacher and Monaco are three terms that fitted well together after the infamous Rascasse incident in 2006, and can be applied again in 2010 after the German overtook Fernando Alonso just before the end of yesterday's grand prix.

Schumacher was penalised for overtaking Alonso, who was running sixth at the time, under safety car conditions. The 20 second penalty handed out demoted the seven-time world champion to twelfth place, and so he left Monte Carlo without any points.

Under new rules introduced this year, drivers do not now have to wait until the crossing the start/finish line to resume racing when the safety car leaves the track, but can now overtake after crossing the so-called safety-car line, which is by the pit lane entrance.

Replays clearly showed that Schumacher passed Alonso after this line, and so the initial reactions to the manoeuvre from most of the viewing public was that it was completely legitimate, and a great piece of opportunistic driving.

However, Schumacher was punished under article 40.13 of the Formula 1 sporting regulations, which states:

“If the race ends while the safety car is deployed it will enter the pit lane at the end of the last lap and the cars will take the chequered flag as normal without overtaking

This rule is clearly for aesthetic purposes – it doesn't look great on TV if the winner crosses the line following a souped-up road car, even if it is a high performance Mercedes.

Many will conclude, after reading this rule, that Schumacher was clearly in the wrong, and deserves the punishment dished out by the stewards.

But does he?

Enter Ross Brawn, with a convincing case for the defence. The team principal of Mercedes spoke to the BBC straight after the race and, complete with hot-of-the-press print-outs, put forward a convincing argument for Schumacher's innocence.

First Brawn produced output from the FIA screen which relays messages to the teams. It stated at 15:51, the safety car would be coming in, a signal that would suggest racing could recommence. At 15:52 the track was said to be clear – further indication that is was safe to overtake, and then at 15:53 was the chequered flag.

Brawn argued that the safety car had been called back into the pits before the race had finished and therefore the race was not ending while the safety car was employed – hence article 40.13 was not applicable.

But the Mercedes team principal was not finished there. On live television, just moments after the end of the race, he produced two images taken from Schumacher's on board camera.

The first showed the Mercedes behind Alonso, and a green light ahead on the track. The second showed Schumacher pulling alongside the Ferrari – but not past it – and there was a green flag ahead.

Any racing fan knows what the green flag signifies, but just to clarify, this is the meaning taken from the official Formula 1 website:

“All clear. The driver has passed the potential danger point and prohibitions imposed by yellow flags have been lifted.”

And here the entry for the yellow flag, from the same source, which details how the drivers are restricted under it, and what the waving of the green flag signals the end of:

Indicates danger, such as a stranded car, ahead. A single waved yellow flag warns drivers to slow down, while two waved yellow flags at the same post means that drivers must slow down and be prepared to stop if necessary. Overtaking is prohibited.”

Clearly with the marshals waving green flags at the drivers, they will interpret this, quite rightly, as a cue to try and overtake.

Like I said, this is a convincing argument from Brawn.

Mercedes say that they will appeal the decision, and the punishment may yet be overturned. Even if it isn't, the FIA will have some questions to answer:

Why is there a rule penalising Schumacher on the final lap of the race, when if he had performed the same overtaking manoeuvre under the same circumstances on any other lap of the race, he would not have been punished?

If overtaking was forbidden for the remainder of the race, why were green flags and lights being shown to the drivers once the safety car had gone in?

Why were the teams informed that the safety car was coming in and that the track was clear when the race was finishing under the safety car?

Couldn't the safety car have just entered the pits on the final lap, as teams and drivers would expect from Article 40.13, without this confusing message being sent out?

Ross Brawn has a good record for appealing to the FIA, and the Mercedes boss will be hoping that his argument will cause them to overturn the steward's decision this time.

After the inaugural Malaysian Grand Prix in 1999, he convinced the court to overturn the punishment handed out to Michael Schumacher and Eddie Irvine for running oversized barge boards on their Ferraris. The team's one-two finish was reinstated and Mika Hakkinen had to wait until the final race of the season to be crowned world champion.

He may not have added to his record number of race wins, podiums, pole positions, or fastest laps since his return to Formula 1, but at least now we are seeing another familiar aspect of Schumacher's previous career return: the ability to court controversy.