The research, published by the U.K. government's Social Mobility and Child Poverty Commission suggested that the hiring bias of firms has created a "class ceiling" in elite firms.
"This research shows that young people with working-class backgrounds are being systematically locked out of top jobs. Elite firms seem to require applicants to pass a 'poshness test' to gain entry. Inevitably that ends up excluding youngsters who have the right sort of grades and abilities but whose parents do not have the right sort of bank balances," the chair of the commission and former Labour cabinet minister, Alan Milburn said.
The research is the product of extensive interviews with staff from 13 elite law, accountancy and financial services firms, which combined are thought to be responsible for 45,000 of the best jobs in the U.K
Dr. Louise Ashley of Royal Holloway University of London, who led the research project said the findings showed that recruitment and selection processes which favor students from more privileged backgrounds "remain firmly in place at most elite law and accountancy firms".
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One anonymous professional interviewed for the survey admitted that he was from a "working class background", but that he rarely spoke of his state school education, as he was "embarrassed".
"It's embarrassing to say that you didn't come from a middle class background. It's embarrassing to say, it shouldn't be, but it is . . . because the City is full of people all the same, right? So, for me to say that my dad was a labourer and I had free school meals at school, it's embarrassing. I feel embarrassed," the interviewee said.
Young people with degrees from the "Russell Group" of universities, including Oxford and Cambridge, were also found to be in with a better chance of getting a job at top-tier firm than candidates with top grades from other universities.
One recruiter working for an elite law firm said the main reason they did not look for graduates from less prestigious universities was simply a matter of budget, as the recruitment process would be much more difficult.
"For us it boils down almost to a budgetary one, being frank about it," the recruiter said.
"Is there a diamond in the rough out there at the University of XXXX? Statistically it's highly probable but the question is, how much mud do I have to sift through in that population to find that diamond? We've got a finite resource in terms of people hours and finite budget in terms of cost to target there," the recruiter added.