The Equal Opportunities Commission has backed two male would-be MPs in their legal action against the Labour Party's policy of women's quotas for parliamentary candidates.
The EOC has taken the controversial step of offering financial help and expert advice to Peter Jepson and Roger Dyas Elliot, whose joint case against Labour will be heard at Leeds industrial tribunal on 11 December.
The case could be a serious embarrassment to the Labour Party, but the commission believes that it is "a matter of public interest" to test the legality of the policy, a spokesman said.
It decided to make a "limited offer of assistance" last week and wrote over the weekend to Mr Jepson, who is acting for both men, offering access to its database of cases and to pay for him to seek further legal opinion.
Mr Jepson was excluded from an all-women shortlist to choose the candidate for the new safe Labour Regent's Park seat in central London; Mr Dyas Elliot was turned away from the selection process in Keighley, West Yorkshire.
Mr Jepson, a PhD student and part-time law lecturer, claims that Labour's policy is in breach of both the Sex Discrimination Act and the European equal treatment directive.
The Labour Party is taking the case seriously and will be represented by James Goudie, a senior QC who once shared an office with Tony Blair, the Labour leader, in the chambers of Lord Irvine, the shadow Lord Chancellor.
"I think that shows they are concerned with the case," said Mr Jepson, who welcomed access to the EOC's research back-up and expertise in equal opportunities case law as a way of matching Labour's legal firepower. Mr Jepson does not have formal legal representation, although he does have voluntary help from a newly qualified barrister.
Mr Blair has been unenthusiastic about the policy of requiring local Labour parties to choose female candidates in half of all winnable seats. In July he said that the policy, brought in by John Smith in 1993 but opposed by the party's former leadership, Neil Kinnock and Roy Hattersley, was "not ideal at all", and he said it would apply only to the coming general election. He later said it would be up to the party as a whole to "review" the policy after the general election.
Alan Lakin, the EOC's chief legal adviser, yesterday denied that the commission had changed its position. The commission, which is charged to "work towards the elimination of sex discrimination" and to monitor the 1975 Act, obtained counsel's opinion last year from Michael Beloff QC that Labour's policy was lawful - "which remains the view of the commission", he said.
The case will turn on whether political parties have a blanket exclusion from the provisions of the Act, or whether being an MP is "employment" - access to which is controlled by the Labour Party in safe seats.
Meanwhile, Labour's National Executive is continuing the slow process of imposing all-women shortlists on reluctant local parties.
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