One of London’s top law firms has been hit with an age discrimination claim from a former partner in one of the first cases of its kind since new rules were introduced last year.

Peter Bloxham, 54, the former head of insolvency at Freshfields Bruckhaus Deringer, filed the claim against the City firm at a London employment tribunal ahead of a deadline yesterday, his lawyer said.

He was one of about 30 lawyers who opted to retire from Freshfields’ partnership on a full pension late last year, instead of remaining a partner and accepting a significant cut in retirement benefits.

Jo Keddie, a partner at Dawsons solicitors representing Mr Bloxham, confirmed that he had filed a claim "on the grounds of age discrimination" but declined to comment further.

It is thought that Mr Bloxham’s claim relates to the fact that Freshfields’ pension cuts affected partners differently according to their age at the time the changes were implemented.

Freshfields declined to comment on Mr Bloxham’s case or to say whether any other former partners had filed similar claims. It has previously said that the majority of the retiring partners had opted to remain as salaried consultants at the firm.

The UK adopted a European law banning discrimination on the grounds of age on October 1 last year. Since then, about 250 claims have been filed, according to the Employment Tribunals Service, but Mr Bloxham’s is thought to be the first against a law firm.

Although, Mr Bloxham’s claim relates to pension provisions, employment lawyers say that law firms, which are almost all structured as private partnerships, could be the subject of a barrage of age discrimination claims because of the way partners are remunerated.

Most UK law firms use a system known as lockstep, where a proportion of partners' pay is set according to how long they have been at the firm, regardless of how much work they actually do.

Lawyers believe that, since older partners are disproportionately more likely to benefit from this system, younger partners may be able to issue age discrimination claims.

Clive Howard, an age discrimination lawyer at Russell Jones & Walker’s said: "The Freshfields case is just the tip of the iceberg. Law firms across the board appear to have underestimated the impact of the new legislation."

"The traditional ways in which some law firms organise partnership and other promotions, reward performance and take recruitment decisions based on the number of years experience that a lawyer has are all now potentially discriminatory on grounds of age.

"It may seem a great irony that one of the world's largest law firms is facing a claim for age discrimination. In truth, it simply reflects a wider picture throughout the legal profession."

The lockstep system is much less popular at US law firms, which tend to employ an "eat what you kill" model, where all partners, regardless of age or length of service, are rewarded for the amount of business they generate and carry out.

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