Do appearances count any more in public life? The formality and elegance so often associated with official British sartorial codes in the past have no place in our undeferential times. In a bid for the simple aesthetic sometimes favoured by Milanese designers such as Miuccia Prada, from today all judges have been ordered to wear “the new civil gown without a wig (or bands, wing collar or collarette)”. Circuit judges are instructed to retain “their existing gown and lilac tippet”, but wigs, bands and wing collars are similarly forbidden, as they are for barristers and solicitors sitting in a judicial capacity.

The new civil gown incorporates an ingenious ranking system - reminiscent of 1960s science fiction - where tabs at the neck indicate status: gold for the Court of Appeal, red for the High Court, pink for the High Court Masters group and blue for district judges. I find it pleasing that the Masters group, which includes bankruptcy registrars and costs judges, should be asked to sport the pink. It adds a pretty note of levity at a moment when bankruptcy cases are presumably on the rise.

In all other respects the news brings little cheer. The Lord Chief Justice's direction also includes an amendment that “High Court judges hearing criminal cases shall wear the winter criminal robe year-round. Scarlet summer robes are no longer issued or worn.” It pains me to think of those great British beaks, the imposing anti-heroes of Bleak House and Trial by Jury, reduced to seasonal monotony, stripped of their scarlet, their wing-collars and their Hogarthian horsehair wigs and forced into a colour-coded overall.

The trend has been evident in other British institutions. The drama and romance of traditional uniform has been jettisoned gradually for a banal and cowardly version of uniformity. In the Square Mile the rot set in when the last bowler hat was hung up during the financial and social turbulence of the early 1970s. Smart City suiting, the subtle Savile Row armour associated with the old-fashioned chivalric values of the merchant bank, gave way either to the scuffed black shoes and sagging, thin black socks of Big Bang deregulation, ERM humiliation and latterly the credit crunch, or the indignities of dress-down Fridays imposed by American management theorists. Chinos and an unbuttoned gingham shirt inspire neither confidence nor respect.

As I watched those made jobless by the collapse of Lehman Brothers commiserating in Canary Wharf, I was struck by the way in which the powerful image of the City trader has fallen prey to the homogenising effects of sartorial globalisation. Interviews with traders experiencing the same loss in New York revealed identical “smart-casual” wardrobes. Things were very different at the last great crash when the sharp lapels of Wall Street in 1929 were utterly alien to the morning-suited reserve of Threadneedle Street.

Does this shift to undifferentiated informality matter? The classic definition of uniform isolates three principles that contribute to the power of a well-regulated and symbolically loaded outfit. The first is hierarchical: it demonstrates rank and demands respect. The second is seductive: allure and magnificence count - we all love a man (or woman) in uniform. The third is utilitarian: well-designed uniforms enhance our ability to do the job, whether by boosting morale or easing the movement of our bodies.

Societies understood this in the past. Many of them introduced sumptuary laws to ensure that both occupational and fashionable dress were tied to social status (though these were usually unsuccessful - such is the power of fashion). In our supposedly more egalitarian, less deferential century the link between clothes and rank has weakened and the first principle of uniform has become irrelevant. That's no reason, however, to let go of the second two; judges and bankers take note.

But perhaps we simply get the uniforms we deserve. During my time at the Victoria and Albert Museum the designer Margaret Howell has created new outfits for V&A gallery warders. Like the fearsome park-keepers of my childhood, warders - often retired soldiers or policemen - used to be fitted out in peaked caps and dark, brass-buttoned blazers. Their job was to protect the valuable objects in their care by surveying and controlling gallery visitors. The forbidding uniform reflected their regulatory function. Now gallery staff are decked out in Howell's informal combination of teal-coloured jumper and cotton-ticking striped shirt, inspired by the colours and textures of the Museum's collections and manufactured by British companies John Smedley and Sunspel. The new generation of warders work as hosts as well as custodians and their clothes contribute to this dual role. True to the spirit of a successful modern uniform they engender a sense of belonging and pride, but fall short of bombastic jingoism.

The same cannot be said of our forthcoming exhibition, Magnificence of the Tsars (December 10, 2008, to March 29, 2009), which will display the elaborate uniforms of the Russian court from the 1720s to the early 20th century. But, as with my lament for the passing of Hanoverian glory in the robing of our judges, I fear that on viewing the gorgeous braid and fringes of Tsarist lackeys I will wax nostalgic for the imperial splendour of St Petersburg. A good old-fashioned uniform can still have that effect.

Christopher Breward is acting head of research at the Victoria and Albert Museum

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