The policy paper is intended to tackle the future of grant-maintained schools, most of which want to retain control over the process of selecting pupils. A growing number of opted-out schools are applying to the Department for Education for permission to admit a greater proportion of students on the basis of academic tests.
David Blunkett, Labour's education spokesman, this week rejected the prospect of requiring schools to have admission policies that ensure a mixed ability intake. The suggestion in a paper from the Fabian Society, a Labour think-tank, that schools be required to take set proportions of children banded in three ability groups (a system used by the former Inner London Education Authority) is considered by Mr Blunkett to be incompatible with parental preference.
According to Mr Blunkett's office, such a system also has the disadvantage that the selection process would require some form of grading of 11-year-olds with unfortunate consequences for those in the bottom group.
However, within the party there is criticism of existing admission arrangements that mean access to popular schools is mainly determined by geographical proximity.
Fiona MacTaggart, a former Labour councillor in the south London borough of Lambeth, and one of the Fabian authors, believes inequality in the distribution of education has grown because middle-class parents are better able to get their children into schools of their choice.
Unpublished research from the National Foundation for Educational Research suggests there is a great deal of variety in the way schools select pupils, but most over-subscribed schools take account of the distance parents live from the school.
The study looked at 10 local authorities, and while around 90 per cent of parents were not unhappy at the choice of school, those parents that had to settle for other schools felt deeply about the issue. Other research from the Open University suggests that around a third of parents feel that they are not provided with any choice.
Labour is aware of the problems of imposing admission policies on schools; voluntary-aided as well as GM schools are keen to retain the power to decide the basis of selection. The decision by the Labour leader Tony Blair to send his eldest son to a GM school that selects on the basis of interviews adds to the difficulty of drafting policy in this area.
Labour's paper has also to spell out what is meant by the phrase "local democratic framework". A policy document published last summer pledged to bring GM and LEA schools within a single framework of accountability, the meaning of which remains unclear. It may be that Labour intends to bring opted-out schools within the planning powers of local authorities, but they will retain control of their budgets.
Mr Blunkett has already made clear that GM schools will not retain any financial advantage. It is unclear whether local authorities will be able to require GM schools to conform to the admission arrangements of other schools.