Personal details from the next census could be disclosed to US authorities if an American defence company wins the contract to run it, the Treasury Select Committee says today. MPs on the committee are demanding that the Government seeks firm assurances that detailed information about the UK population will not be at risk of being handed to US intelligence agencies.

Today’s warning over census privacy comes in a report on counting the population that also condemns the a survey for measuring migration as “not fit for purpose”. The International Passenger Survey, which defines an immigrant as someone staying in this country more than a year, based its 2005 estimates on interviews with 2,965 people arriving and 781 departing.

It interviewed just 94 citizens from the eight former Soviet bloc states who joined the European Union in 2004 and 90 per cent of all interviews took place at Heathrow.

Michael Fallon, a senior member of the committee, said: “It is now impossible to estimate accurately the UK population today. We heard evidence that local authorities including Westminster, Slough and Manchester, have experienced difficulties where inaccurate statistical data resulted in reduced allocation of financial resources.

“Our democracy is dependent on accurate, independent statistics. It is essential that when we consider important national issues we can rely on the data that is provided.”

Two companies, Lockheed Martin, the US defence group, and the German telecommunications company TSystems, are bidding for the £450 million contract to run the 2011 Census.

The US Patriot Act allows personal data held by companies in the US to be made available to the intelligence agencies.

Angela Eagle, a Treasury minister, said that if Lockheed won the contract, provisions preventing the removal from the UK of census information would be put in the contract, but MPs on the Commons committee were not convinced.

“We remain concerned that the personal information gathered throught the 2011 Census could be subject to the United States Patriot Act and therefore we ask the Government to take clear legal advice and advice from the US State department and to publish it,” the Treasury Select Committee report says today.

Lockheed Martin’s involvement in the census in Canada in 2006 fuelled protests leading to the creation of a new privacy taskforce there.

The 2002 Patriot Act increased the powers of US law enforcement agencies to monitor telephone and e-mail communications to combat the threat of terrorism. It has been criticised as infringing civil liberties.

The 2011 Census could be the last survey of its kind. There are growing concerns that it no longer provides reliable data on which to base public spending decisions, given Britain’s rapidly shifting population and the levels of immigration.

Today’s report condemns the mid-year population estimates for England and Wales and the International Passenger Survey, the study which has the central role in estimating international migration.

“It is clear from the evidence we have received that this survey is not fit for purpose”, the Treasury Select Committee concludes.

Of the 2005 passenger survey, the report criticised the small number of people interviewed. “This was a very small sample and suggest why there were large uncertainties surrounding the official migration numbers,” the report said.

Very few interviews took place at Stansted and Luton, where many flights from the new EU states arrived. It was not clear if any interviews took place at Victoria coach station in London, where thousands of East European migrants arrived by bus.

“The IPS may also fail to accurately measure international migration as the survey was not designed to measure net migration but was designed to capture tourism and business travel; participation in the survey is voluntary and immigrants may be less likely to respond (perhaps because of language barriers), and the survey asks about intentions on arrival, not what people actually do,” the report said.

The Bank of England told the committee that there was a risk that the current estimates were underrecording the true population.

Earlier this week the Office for National Statistics revised upwards its estimates for the number of immigrants coming into Britain for less than a year.

Migrants to Britain

22% Increase in estimate for migrants coming into Britain for less than a year in mid-2005

23% Increase in estimate for migrants coming for less than a year in mid-2004

1.2m Short-term immigrants arriving in 2005

1.1m Short-term immigrants arriving in 2004

1.7m Estimated immigration including short and long-term migrants in 2005

1.5m Estimated number of short and long-term migrants in 2004

Source: Office for National Statistics

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