OXFORD University is positively discriminating in favour of state school students, giving the lie to charges of elitism in the wake of the Laura Spence affair, it was claimed today.

An analysis of undergraduates' A-level grades showed that while most needed three As to get in, 23 per cent of comprehensive pupils got a place with less, compared with 17.2 per cent from fee-paying schools.

Liberal Democrat higher education spokesman Evan Harris said the figures showed Chancellor Gordon Brown had been wrong to accuse Oxford of elitism, when he attacked as "scandalous" Magdalen College's refusal of a place to North-East teenager Laura Spence.

Her case sparked outrage after the pupil, from Monkseaton, North Tyneside, was denied a place at Oxford to study medicine, only to win a scolarship to Harvard and later get five A grades.

Most undergraduates who got in with less than three As achieved two As and a B, equivalent to 28 points on the scale used by the Universities and Colleges Admissions Service, where an A is worth ten points.

However, the number of state school pupils who are admitted with less than two As and a B was twice as high - 6.7 per cent - compared with 3.3 of independent school pupils.

A spokeswoman for the university said it did not have a general policy on how offers were made, but was committed to "selecting the brightest and best candidates, whatever their social or educational background".

The findings, which cover 1999, emerged after provisional figures from the university showed that comprehensive pupils were winning more places there than their fee-paying rivals for the first time in recent years.