THE man blamed for last year’s school testing fiasco is to break his silence and accuse Ed Balls, the children’s secretary, of misleading the public by denying any responsibility.

Ken Boston, former chief executive of the Qualifications and Curriculum Authority (QCA), will contradict claims by Balls that he bore no responsibility for the shambles that disrupted the education of tens of thousands of pupils.

Instead, he is likely to tell MPs that ministers were “active participants” and “in no way at arm’s length” as the problems of tests multiplied.

Boston is also expected to say that he warned ministers for years that a disaster was possible. Boston’s appearance, after a long enforced silence because of his employment conditions, will increase pressure on Balls, who has largely shifted blame by arguing he played only an indirect role.

Boston has previously warned there is a “high risk” of failure this year. Pupils are to sit their Sats next month but there are signs the test system is crumbling. Balls scrapped compulsory tests for 14-year-olds after last year’s crisis. The National Union of Teachers, which has long opposed tests, is exploiting the disarray by balloting for a boycott of the 2010 round for 11-year-olds.

Boston could not be reached for comment this weekend, but one former colleague said he had been eager to put his case since an official inquiry “stitched Ken up” because it had a remit that effectively prevented it from judging Balls’s role. Another friend of the 66-year-old Australian said his appearance was likely to be “pretty bloody” for Balls.

Boston offered his resignation last December following the damning inquiry by Lord Sutherland, but this was turned down and he was instead suspended. His resignation, described as “a tragedy” by the headteachers’ union leader John Dunford, was accepted only this month.

Boston has written to Barry Sheerman, chairman of the Commons schools select committee, asking for the opportunity to make his case. “I will now get Dr Boston in front of the committee,” Sheerman said. “He has been keen to appear and frustrated but now he is liberated from his suspension. We will be making an early appointment.”

Michael Gove, the shadow schools secretary, said: “The department tried to dump on Ken Boston and the QCA. We need his analysis of where responsibility truly lies.”

Last year’s Sats tests, used to compile league tables, were taken by more than 1.2m children aged 11 and 14. However, ETS, the American company that won a £156m contract with the QCA to administer marking, was unable to cope.

There was chaos when thousands of papers were sent to the wrong markers, 100,000 unmarked tests were returned to schools, others were found piled in warehouses, computer systems failed and calls to help-lines went unanswered.

About 30,000 pupils went into the summer holidays not knowing results. For some, this meant an uncertain start to secondary school as staff were unsure what ability set they should be placed in.

When news of the crisis broke last July, Balls told the Commons that Boston had reassured him the previous month that the results were on track. He stated he found out about the delay only on July 1.

He said he had been restricted to monitoring the marking “at arm’s length” because the QCA was an independent agency. Jim Knight, Balls’s deputy, later said: “Only under detailed scrutiny and questioning was it revealed to me [by Boston] that they believed we were not going to hit those deadlines.”

Boston contradicted Balls and Knight in a letter to Sutherland’s inquiry, saying: “Ministers and officials had access to exactly the same data and information as [the QCA]; they were active participants . . . in no way at arm’s length.”

Friends of Boston believe the government has failed to tackle the underlying causes of the failures. “When Whitehall tries to examine every child in the country with the same test on the same day then things are going to go wrong,” said the former colleague. “It was in a fairly subtle way, but Ken made it clear to ministers that this model is not a very good model.”

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