Whitehall departments used to be rated in an annual league table according to how many ethnic minority employees they recruited, and how many were promoted to senior civil service grades.
The rankings, based on government data, were compiled by the old Commission for Racial Equality (CRE). Eventually, Trevor Phillips, its chair, received an anxious phone call from the chancellor.

The Treasury was near the bottom of the table, and Gordon wasn’t too pleased.
Not long afterwards, the government stopped publishing the data in the format that the CRE used to construct its table. It was at that point that Phillips knew he had discovered a powerful weapon for holding employers to account.

Today, Harriet Harman, whose posts include minister for equality, faces some important decisions on discrimination law. A single equality bill, promised in Labour’s 2005 manifesto, is likely to feature in this autumn’s Queen’s speech.

The bill, when it eventually becomes law, will sweep away 40 years of piecemeal regulation against discrimination at work with an all-embracing duty on employers to treat staff fairly regardless of race, gender, age, disability, sexuality or faith.

Phillips, as chair of the new Equality and Human Rights Commission (EHRC), wants to go further by forcing big employers, both public and private sector, to disclose figures relating to the diversity of their workforce. The EHRC would tabulate and publish the results, thus naming and shaming – although Phillips avoids the term – those at the bottom of the list.

Of course the media would have a field day with results showing that Sainsbury’s had more black employees than Morrisons, or that Barclays employed more gay staff than Lloyds. Harman must decide whether to use the single equality bill to grant the EHRC the powers it needs to construct the league tables.

Phillips is right to say that the rankings would do more to encourage firms to promote black, women or gay employees than any number of threatened tribunal cases. The question is: what would be measured? Equality of opportunity, or equality of outcome?

Consider three businesses: a City brokers’ firm where ethnic minority staff have risen to the top, on merit, but the wide-boy culture is hostile to women and gay men; an engineering firm in Sunderland, where the staff are pretty much all white and all male; and a food plant in the West Midlands where the workers, from managers to shop floor, are all Asian.

Which is top of the diversity league? Which is bottom? Does the Sunderland firm have the workforce it does because no one black or female has ever applied? Do we forget the numbers game and rate firms according to their written anti-discrimination policies? In which case, won’t the results be meaningless?

If the EHRC can resolve these questions, and Harman gives the go-ahead, the diversity league could have as big an impact on businesses as exam results tables have had on schools.

It wasn’t a bad joke by Vince Cable at the Lib Dem spring conference – the policy of raising duty on strong booze and cutting VAT on healthy drinks ‘will complete the transformation of the Lib Dems from being the party of beards and sandals to the party of smoothies’.

The idea, intended to help people reach their five-a-day target, won the Lib Dems a bit of much-needed media coverage. Cable was praised by Innocent Drinks, the smoothie maker which has apparently collected 20,000 signatures on a petition calling for such a change.

But hold on a minute. Innocent smoothies cost £7.16 a litre at Tesco, compared with 68p for own-label pure fruit juice. Surely if anyone is well-placed to make healthy food more affordable, it is Innocent, not the government.

Still, with the north London muesli-belt seats of Islington South and Hampstead both among their top 10 targets at the next election, it looks as though the Lib Dems have aimed this tax cut with precision.