Nigel Hawkes: Full disclosure can make some citizens uneasy

Behind The Numbers

Next March's Census will ask a lot of personal questions. As well as finding out who lives where, it will record religious belief, long-term illness, relationships, country of origin, ethnicity, employment and any overnight visitors.

Filling in the 32-page form is compulsory, but in 2001 many people managed to avoid it. If you are an immigrant of questionable status or a recipient of social security payments to which you may not be entitled, tossing the Census form in the bin is quite understandable – even though you can be fined £1,000 for doing so.

The Office for National Statistics (ONS) says all information will be used for statistical purposes only. Counting the population is vital to ensure that, for example, cash is fairly distributed locally by central government.

But since 2001, anxiety about the security of personal data has grown and willingness to fill in forms has declined. ONS is under instructions to do much better than it did in 2001, but won't find it easy. Other major countries, such as the US, have abandoned "long-form" Censuses and when the Canadian government decided to follow suit this summer, the head of its statistical service resigned in protest.

The task has not been made any easier by the drafting of the 2007 Statistics and Registration Service Act. In spite of the huge efforts ONS makes to preserve the confidentiality of information, the act says there are exemptions.

These include disclosures required by EU obligations, for the purposes of criminal investigations or proceedings (whether in the UK or not ) and those made in the interests of national security to an intelligence service.

So it appears that the EU, the police or MI5 can wade through the Census data at will.

When the ONS was asked by Jill Leyland of the Royal Statistical Society to clarify the issue, Director General Stephen Penneck said he would never release data for non-statistical purposes and would go to the highest court in the land to prevent it. Sir Michael Scholar, chair of the UK Statistics Authority, concurred.

Given the wording of the 2007 Act, that's not quite as reassuring as it might be. My reading of the Act, contrary to Mr Penneck's, does not suggest that every request for disclosure needs a court order before it must be complied with.

Rather, it implies that the presumption in the case of these exemptions (and a few others) is that the data must be released.

It's all very odd – and potentially damaging to the success of the Census. Even non-criminals may hesitate to provide data which, as the law stands, could be demanded by any police force in the world. Despite Ms Leyland's useful intervention, I don't think the position has been clarified sufficiently for the Census-takers to rest easy.

And as it's going to cost £500m, the price of failure is pretty high.

Nigel Hawkes is Director of Straight Statistics www.straightstatistics.org