Up to two million people are to have their credit files secretly checked under a crackdown on tax evasion to be unveiled by George Osborne to help raise another £10 billion.
Credit reference agencies will cross-check details of the income people declare on their tax returns against their spending patterns to identify "high" and "medium" risks of both illegal and legal tax avoidance, the Daily Telegraph reports.
People identified to HM Revenue and Customs will then be subject to more detailed investigations. About two million people are expected to be scrutinised under the programme, which may lead to privacy concerns.
HMRC will today unveil the "successful" results of a pilot programme involving about 20,000 people which will now be extended nationally.
Many of those who are expected to be identified are likely to be self-employed workers who have under-declared their income to the authorities.
However, those who have benefited from secret windfalls - such as an inheritance or a bonus - and people with secret offshore accounts could also be highlighted.
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