It has been some week for undercover stings. The latest today sees the Daily Telegraph splash on how exam boards are tipping off teachers to improve student pass rates – and, consequently, their profits.

Telegraph journalists have secretly recorded meetings between examiners and teachers and revealed the miserable extent of corruption at the heart of Britain’s education system. The Independent’s lobbying sting might was awkward and impacted on few (barring a certain measure of hypocrisy a propos someWikipedia editing), but this exposé of exam boards is reprehensible and has extensive ramifications.

The education secretary, Michael Gove described the Telegraph’s revelations as in the “highest interest of public service journalism”. Gove immediately ordered an inquiry from the qualifications regulator Ofqual, which is already investigating separate potential conflicts of interest. It is expected that Ofqual will report back before Christmas. Speed is of the essence because the regulator has said that it could even pull examination papers set for next summer.

In September, I wrote about how exam boards can increase and decrease graded pass rates by a small percentage (either way) each year. Private exam boards’ profits rely to a great extent on schools continuing to pay for their services, therefore it comes as no surprise that those pass rates only rise, not fall.

Again in September, the exam board AQA demonstrated a startling ignorance of schooling and pupils by engaging in naked political grandstanding at the Labour party conference. AQA proposed marking down pupils at independent schools. This is an exam board that, like its competitors, also has a lamentable track record of unreliability.

England has always had a plethora of independent – if not always directly competing – exam boards, going right back to the Oxford, Cambridge and Durham university matriculation boards of the 1850s. There has always been an element of choice for schools but in the past they tended not to shop around.

However, during the 1980s and 1990s the myriad local authority and university exam boards were encouraged by the government to merge, resulting in the small group of large organisations today, which in England are AQA, OCR, and Edexcel. The smaller CIE is controlled by OCR and operates in England, Wales and Northern Ireland. CCEA and WJEC operate in Northern Ireland and Wales respectively, while Scotland has one board, the SQA.

It cannot be said that exam boards underwent a privatisation process during the 1980s and 1990s because they were already independent organisations. There was no monolithic National Coal Board equivalent. Rather, the exam boards underwent a process of rationalisation. Regardless of definition, the end result and the thinking behind this process has been similar to the privatisation schemes. Choice breeds competition, which breeds innovation, lower prices and higher standards.

However, there is no need for market forces in the school examinations system. Unlike utilities, for instance, where valid arguments were made for privatisation and the free market, no argument has ever been made for the private business of public examinations because it never underwent that metamorphosis.

Market forces in exam boards have resulted only in a race to the bottom, driving down standards to the desperate detriment of children’s education. According to the Telegraph, one chief examiner admitted bluntly, “We’re cheating [and] probably the regulator will tell us off”.

Ofqual needs to do more than just tell off the exam boards. Public examinations in this country need a fundamental rethinking. The government seems to acknowledge this, Michael Gove having already described current examinations as “discredited”.

It will be a difficult thing for many people on the government benches to agree with, but what this country needs is a single, independent exam board in place of the corrupt system we have today, with boards chasing customers for profits. In this instance, the free market has failed.