To discriminate or not? That seems to be the question being posed by Harriet Harman, Labour’s deputy leader and equality minister, who launched the new Equality Bill last week.

Ushering in a new era where discrimination in the provision of goods and services is banned (unless of course one group quite likes the discrimination they enjoy: free bus passes for the elderly, discounts for the young, targeted products like Club 18-30, the list of exceptions goes on and on), Harman’s message was that it is no longer acceptable for businesses to treat people differently just because of their age, race, sexual orientation and gender.

But in the same breath she called on employers to discriminate in their recruitment policies in favour of “underepresented” groups in the workforce.

The greatest muddle surrounds this question of “positive discrimination”, itself a mish-mash of good intentions and blurry outcomes. Ms Harman has indicated that, should a company wish, it may legally discriminate between two equally qualified candidates by awarding the job to the person from the ethnic or sexual group that is under-represented in the company.

So if a man and a woman are pursuing the same job, and there are fewer women in the company, the employer can give the job to the woman on the grounds that it is thereby redressing a statistical imbalance.

Similarly, Ms Harman said, a primary school head could discriminate in favour of a male teacher if the school was already heavily dominated by women.

The examples that Ms Harman chose are deliberately anodyne. But the wider principle, when officially championed by any government, is a treacherous one. It boils down to: “You can discriminate on sexual or ethnic grounds if you want to, provided we judge it to be positive.”

There are two problems with this (when you ignore all the obvious inconsistencies of the policy):

The first is that no employer in their right mind turns away the best candidate for the job just because of their gender or race. Faced with skills shortages across the board, employers are grateful to find anyone who can do the work.

The second problem is that with ever more regulations covering recruitment come ever more unintended consequences. Employers have voiced concerns about how maternity rights could influence decisions about recruiting women of child bearing age.  The issue they raise reflects the trade off that employers have to consider between choosing the right person for the job and taking into account whether someone will actually be at work to contribute to the bottom line is perfectly rational - even if adopted as a formal policy it would neither be legal nor morally defensible.

What the Government should focus on is making it easier for women who chose to work to do so. Childcare remains prohibitively expensive for the majority and is not offered in the flexible manner that modern working life requires.

Harman rightly questions why part-time work is so badly paid compared with the full time equivalents. But the reason is surely that demand for this work outstrips the supply. Employers in the private sector that do offer part-time work are simply responding to that market dynamic that exists.

Back to Harman’s call for positive discrimination: the final outstanding question is whether even with this new legislation it will ever be legal for employers to discriminate against men?

The personnel profession, for one, is not convinced. The Chartered Institute of Personnel and Development is not known for challenging the conventional wisdom. But last week Dianah Worman, diversity adviser for the CIPD was openly questioning what planet Ms Harman is on.

“Positive discrimination is illegal - you can’t appoint someone to a job just because they are from an ethnic minority or because they are a woman,” she said.

It is this uncertainty that needs to be clarified before employers start taking Labour’s latest foray into social engineering seriously.