Gordon Brown's closest Cabinet ally is embroiled in a row over Government spin.
Children's Secretary Ed Balls was accused of trying to "bury bad news" of figures that showed nearly a fifth of pupils were denied a place at their preferred secondary school this year.
He released the figures at the same time as making a high-profile statement that "a significant minority" of schools were breaking the law, with some charging parents "many hundreds of pounds" for what should be a free education.
Mr Balls' claims - based on unverified research - made headlines across national and regional media but the official admissions figures received less coverage.
The statistics watchdog has now written to civil servants in Mr Balls' department and stressed that the release of official figures should be "seen to be independent from policy comment" as a matter of "public trust".
Shadow Children's Secretary Michael Gove said: "Yet again the Government has been caught out trying to bury bad news. It is important that schools abide by the admissions code but ministers have admitted that their investigation was incomplete and unverifiable.
"So why did they release the results so quickly, to coincide with the news that one in five parents don't get their choice of school for their child? Gordon Brown promised an end to cynical spin operations like this but they continue to thrive."
The Statistics Commission said it could not rule out the possibility that the media coverage of the actual figures would have been different if Mr Balls had not made his statement about schools breaking admissions rules.
Statistics Commission chief executive Richard Alldritt said: "We would be concerned if ministerial statements, issued at the same time, distracted attention from new statistics."
Mr Alldritt said he did not think Mr Balls' statement that schools were failing to comply with admissions laws had distracted "much" from the coverage of the figures.
