http://www.liberty-human-rights.org.uk/pdfs/policy12/liberty-s-submission-to-the-draft-local-audit-bill-committee-oct-2012-.pdf
If this issue affects you, write to your MP asking them to read and to support Liberty's evidence. You might need to download it because it has not appeared on Parliament's web site yet.
This passage appears to me to sum up what is happening with the electoral register matches, especially with the rising 18s report:
See also the comments hereData thrown up by these technologies, often without any initial human intervention, will inevitably highlight entirely innocent activity as patterns which appear suspicious. These kinds of data processing carry the clear potential to mislead, given that they operate, by necessity, on the basis of simplistic generalisations about human behaviour or stereotypes about the implications of personal characteristics.
http://www.liberty-human-rights.org.uk/pdfs/policy07/serious-crime-bill-2nd-reading-commons.pdf
If people who have done nothing wrong feel that they are nevertheless being targeted by the criminal justice system the effect could be disastrous. We fear that these schemes will corrode the public faith and trust that is vital to the effective administration of justice in this country.
Well done Liberty! Now we need Big Brother Watch to get involved with this one: it is right up their street. If they thought National Identity Cards were a bad idea, the sort of massive and intrusive state database which Part 6 paves the way for will have them very worried.