It follows a long running dispute between the governors and former head teacher at the Gilbert School in Colchester.
Mr Blunkett wrote to education secretary Gillian Shephard asking for more information about the situation at the school. Her reply said that any problems had now been resolved.
But Mr Blunkett said it highlights lack of accountability within grant maintained schools.
'I hope we can avoid it by putting education not only at the top of the agenda but putting accountability to the community at the top of the agenda if we are elected next spring'.