Last week's Institute for Public Policy Research report on school admissions articulated what many had long suspected: that many schools which control their own admissions are using this power to select in more affluent, high-performing pupils and keep out those from less advantaged backgrounds.
The result: socially segregated schools and increasing educational inequality, due in part to things called "peer group effects" - the phenomenon by which pupils do better when they have a concentration of high-performing peers in their class.
You can't blame the schools for maniuplating the system, given the twin pressures of Ofsted and league tables. The question is, why does the government want to not only keep the current arrangement, by which foundation and voluntary aided schools, which make up one-third of English secondaries, control their admissions, but increase the number of schools in this position?
Its drive to create 400 city academies and persuade other schools to acquire semi-independent trust status will make a bad situation worse.
Sure, the government has toughened up the school admissions code to prevent the sort of covert selection highlighted by IPPR.
However, the think-tank's Richard Brooks described this as "like asking pupils to mark their own essays, while providing them with detailed rules designed to prevent them from cheating".
The reason for the government's stance seems to rest in the peculiarities of New Labour and its attitude to public services: notably its abiding fear that the middle-classes are set to quit state-funded services for the private sector, and its belief that public services must be reformed to prevent them from doing so.
Just as schools are incentivised to favour a concentration of better-off pupils, so better-off parents have a tendency to favour schools that are socially segregated in their favour.
I have no idea if the accession of Gordon Brown is likely to change any of this but it would be nice to think that he would consider taking on board the IPPR's recommendations: transferring responsibilities for admissions back to councils and in the long-term deciding admissions by fair banding, through which all schools are allocated pupils from a mixed range of ability across an area.
What price equality of opportunity, Gordon?