Wealthy pupils have an “unfair advantage” under a generous GCSE re-marking system that sometimes upgrades students’ scores even though the original mark was valid, a senior director at the exams watchdog Ofqual has said.

Dr Ian Stockford, Ofqual’s executive director for general qualifications, told a conference that re-marks of exam scripts sometimes led to “legitimate marks” being upgraded - because long-answer questions required a degree of personal judgement from the marker.

Those who can afford to pay for papers to be reviewed - in order to exploit this situation - could have an advantage, therefore. Exam boards charge a fee for papers to be re-marked, but return the fee if the grade is changed.

“Schools or parents who can afford to pay for a review of their marks may be given an unfair advantage, not because they are getting marking errors corrected that they wouldn’t otherwise but simply because they are seeking a legitimate mark that they have been awarded to be overturned,” Dr Stockford said.

He explained that marking long answers required an element of professional judgement and different examiners could legitimately award different marks to the same answer. In some cases, long answers were marked more generously on re-mark even though the original mark was “a perfectly reasonable interpretation of the mark scheme.”

In comments that will be interpreted as a sign that the watchdog plans to tighten the rules on re-marks, Dr Stockford said: “In the current system, exam boards rightly correct genuine marking errors but they can also sometimes change legitimate marks.

“This can give a misleading impression about the number of marking errors made.”

He said this had raised “significant concern” at Ofqual.

Ofqual is due to open a public consultation on marking quality later this year, after a series of increases in the number of GCSE and A-level marks being challenged. The latest figures on the number of challenges are due to be published next month.

Dr Stockford said he “probably [wouldn’t] be giving too much away” in anticipating another rise in re-mark requests.

During his speech, at the Association of Colleges’ annual conference in Birmingham, Dr Stockford said that around 60 per cent of headteachers did not believe the marking of GCSEs was accurate.

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