The return of Jonathan Ross to his late-night TV chat show will be studied with interest by media buffs and brand experts keen to gauge public reaction to the prodigal’s homecoming, as reputation management specialist Darren Smith explains.

The outbreak of “foot in mouth” disease that afflicted Jonathan Ross last year is the latest in a chain of verbal blunders that could redefine the old adage that there is no such thing as bad publicity, according to a top brand image lawyer.

Ross returns to the TV screen this Friday after a three-month exile for overstepping the boundaries of decency during the now-notorious Russell Brand radio show in which they left sexually charged messages on comic actor Andrew Sachs’s telephone answering machine.

No doubt the first programme in which he reclaims his familiar timeslot will attract record viewing figures, as Britain tunes in to see whether his months in the wilderness have left him chastened. But whether the comeback booms or bombs, it seems likely that both his reputation, and that of the BBC, which has been criticised over the handling of the issue, have been permanently tarnished.

Darren Smith, head of the risk and liability practice with Birmingham-based law firm Hill Hofstetter, said: “There have been a number of incidents in recent years where unguarded comments have received massive publicity, resulting in enormous damage to the reputations of businesses and individuals.”

Way out in front is the blunder by High Street jeweller Gerald Ratner, who famously described his own products as “crap” during a speech to the Institute of Directors in 1991.

Coming a close second was the remark by Barclays chief executive Matt Barrett, who admitted in evidence to a Commons Treasury select committee in 2003 that he did not use credit cards issued by his own subsidiary, and that he advised his four children to have nothing to do with them either.

More recently, says Mr Smith, the demise of the ill-fated Lapland West Midlands and Lapland New Forest parks, was accelerated by the speed at which bad publicity was circulated, thanks partly to the reach of the internet.

Mr Smith added: “They used to say there was no such thing as bad publicity, but I’m not so sure any more.

“It doesn’t take a lot to damage a reputation, and with the reduction in consumer spending, any damage to a business brand – which may once have been merely embarrassing – could now be fatal.

“There is also a big question mark over the way people value their brands,” he said. “It is possible to devalue a brand, and there is some suggestion that this is what happened to Marks & Spencer in the run-up to Christmas, with their 20 per cent off sale, which seemed to have little effect.”

Even international fashion brands can sometimes lose the plot, he points out.

At least one major fashion house, renowned for producing handbags costing thousands of pounds, has been advertising that it also targets women with just hundreds to spend.

“One of the reasons people buy these luxury goods is that is it a statement of affluence. By making them cheaper they risk losing their market.”

Conversely, he says, there is evidence of a new trend among the well-heeled, making it chic not to flaunt extravagant spending.

“That could account for the fact that while retailers such as Next and Debenhams are seeing a downturn, chains such as Primark and New Look are experiencing an increase in sales,” Mr Smith said.

“Companies should ensure they have a clearly defined brand. Part of the reason people didn’t go to Woolworth’s was because they didn’t really know what the store was about any more.

“The same applied to Adams, the childrenswear store which went into receivership over Christmas. They were stuck in a poorly-defined grey area between Next, which sells expensive children’s clothes, and Tesco’s own brand at the budget end, and they didn’t have anywhere to go.”

Mr Smith believes companies might weather the recession better if they follow the lead set by Marks & Spencer during the last slump, in the 90s.

“They bought from British manufacturers and suppliers, and supported British jobs,” he explained.

“The only retailer I know of that does that today is Wilkinson’s, a family-owned firm. They tell you how many British jobs they are supporting.”

He added: “It worked for M&S last time around and it might be something that other companies could copy.”