Formula 1 World Championship leader Lewis Hamilton 'did nothing wrong' in the Belgian Grand Prix and the sport's FIA-designed rules are 'one-sided', argues Sir Jackie Stewart - even though McLaren team principal Ron Dennis insists there has been no unfair treatment of his driver in 2008.

Arriving in Singapore for F1's inaugural night grand prix this weekend, Hamilton holds just a slender one-point margin over Ferrari rival Felipe Massa in the drivers' title chase, following his and McLaren-Mercedes' unsuccessful bid to get the British star's Spa-Francorchamps penalty overturned at the FIA International Court of Appeal earlier this week. Former three-time world champion Stewart is adamant justice was not done.

"He did nothing wrong in Belgium," the Scot stressed in an interview with the Daily Mail, "and Niki Lauda agrees with me on that. The rules are written in such a way that they are one-sided and appeals are doomed to failure. That isn't Lewis' fault but the FIA's. They have to get it sorted.

"These kind of decisions are simply not consistent. I strongly believe there has to be a look at the governance of the sport. To be blunt, you are talking about part-time amateurs (the race stewards) who have a huge amount of influence over the sport. We have to change that, otherwise the sport risks losing all credibility.

"What we need is the appointment of full-time stewards, who are directly accountable to the FIA, just as Premiership football referees are accountable to the Football Association, or tennis umpires are accountable to the ATP and WTA.

"It's beyond my comprehension why the multi-national companies who pour millions of pounds into F1 are content to let this situation stay as it is."

Stewart - who claimed the crown for Matra in 1969 and Tyrrell in both 1971 and 1973 - did, however, tip Hamilton to bite back in Singapore, pointing to the 23-year-old's supreme mastery of wet conditions that has already seen him prevail at Fuji, Monaco and Silverstone during his fledgling career in the top flight to-date as a significant advantage during what looks likely to be a rain-lashed weekend.

"Hopefully, Lewis will use this setback positively," the 69-year-old stated, suggesting the Stevenage-born ace will use his failed Spa appeal as a spur to dominate proceedings in the Far Eastern city-state. "He is still in the lead in the championship and has shown that when the weather is wet - and rain is forecast for Singapore - that he has the temperament and talent to excel."

Meanwhile, Ron Dennis has underlined that he is confident there is no conspiracy theory against Hamilton and McLaren this year, as some have claimed.

"Although Lewis has had five penalties already this season, I wouldn't say that he hasn't been treated fairly," the 61-year-old affirmed.