In the dock stands the diploma, the Government's qualification of choice. The defence is led by diploma champions from business, higher education and education in general: heavyweights such as Professor Michael Arthur, vice-chancellor of Leeds University, Sir Alan Jones of Toyota, and the ubiquitous Sir Mike Tomlinson. On their side are a number of employers and university vice-chancellors.
For the prosecution, a growing band of academics - professors Alison Wolf and Alan Smithers among them - at least one teachers' union (Voice), an awarding body chief (Jerry Jarvis), a leading maths advisory group (Mathematics in Education and Industry) and, in June, the Confederation of British Industry's director general, Richard Lambert. This last detractor is proving tricky for the defence because the CBI changed sides over the summer - it had previously publicly backed diplomas.
In the middle, in the dual role of jurors and potential victims, are the mass of England's 14 to 19-year-olds and their parents. For this is a trial in which Scotland, Wales and Ireland - north and south - want no part.
The prosecution leads. Against the diploma is stacked a formidable list of charges. First, confusion of purpose: neither fish nor fowl, neither truly vocational nor academic. Diplomas aim simultaneously to attract the disaffected and motivate the gifted.
Second, an over-complex design: with 17 diploma lines across three levels and variants at advanced level (the progression award and extended diploma), the qualifications give Heinz 57 a run for their money. Few outside the Department for Children, Schools and Families will understand them, certainly not employers. Moreover, with an average of 10 groups involved in each partnership, diplomas are destined to be the most bureaucratic qualification ever designed.
Finally, complexity of delivery: no individual school or college can teach a diploma on its own. Elaborate and bureaucratic government-controlled, - appointed and -funded consortia are the chosen model for teaching them.
Enforced regional partnerships, involving complex plans to bus students and staff around, look set to scupper the qualification before it has got off the ground. The announcement in June that pound;23 million is being provided by the Government to help rural areas cope with the logistics was a real gift to those against the diploma.
For the defence, a laudable array of hopes and aspirations, but little of substance and no hard evidence. Diplomas will, it is claimed, keep all learners in education and training until 18, a key part of the Government's strategy for tackling the so-called Neets (not in education, employment or training). They will also, it is alleged, open doors to the most prestigious courses at the top universities. They must, come hell or high water, guarantee the "basics" of literacy, numeracy and IT skills while developing broader skills for work, study and life. They should, fingers crossed, keep options open so students can progress to employment or degree-level study in a related field.
Last, and most sinister, they may eventually subsume or replace existing vocational qualifications such as Btecs and even their academic counterparts, A-levels, although no one in official circles is honest enough to admit to it.
Innocent or guilty? How would you vote? Let's be clear: no one wants the diploma to go down. If it does, it will be for a long stretch and it will leave a gaping hole in this Government's shaky 14-19 strategy. But its fate hangs in the balance. This September, some 20,000 courageous young people will trust their futures to this Government's untried and untested diplomas. For the first cohort, this is both a pilot and "for real". Would you want your son or daughter to take part? How many children of politicians and civil servants in Whitehall are signed up? (I suspect we know the answer to that one.)
For maintained schools and colleges, participation will not be optional. "Entitlement" for students will rapidly turn into compulsion for schools, backed by hard financial incentives. The Government's "qualification of choice" will become schools' "qualification of compulsion". Yet this is at a time when, for the rest of the UK and schools in the independent sector, there is an increasing range of rich and stimulating options that avoid the confusion of the diploma.
Many of the qualification's most positive features, such as the "extended project" - designed to develop skills of independent research - are available without having to commit to the diploma as a whole. The Cambridge Pre-U, the international baccalaureate, the Welsh bac, the AQA bac - all these qualifications mirror aspects of the diploma that would benefit young people. None prescribes how they are to be taught.
There is also the DIY bac, with schools free to develop their own "group awards" by putting together a curriculum and qualifications package to suit their students' needs, drawing on the best of what is available.
With the jury out on diplomas, the qualification could yet be acquitted if the Government were to act swiftly and decisively. Two things need to happen to save the diploma or at least let it out on bail. First, radically reduce the complexity of its design and delivery. Every previous government initiative on this scale - notably the original national curriculum and Ofsted inspections - has had to be pared down and made simpler.
Second, get rid of compulsion: let schools and the market decide how best to deliver diplomas in their particular circumstances. For example, an independent school paired with an FE college or an employer, or a state school and a university, or even a school or college on its own.
Only then can the new diploma receive a fair trial.
Geoff Lucas, Secretary, Headmasters' and Headmistresses' Conference.