HMRC's impressive new software trawls billions of items of data from dozens of sources in its hunt for underpaid tax – and it's about to have access to even more information, which can be shared with 60 other countries

The offices of the taxman are not usually credited with efficiency and success. But there is one aspect of HM Revenue & Customs which is highly – some would say terrifyingly – efficient, and that is its powerful computer program which is accessing and trawling databases of personal financial information on an unprecedented scale. The software, called "Connect", has been developed at a cost of £80m over seven years. Its basic job is to scour vast databanks of personal and commercial information, seeking to unearth links between individual taxpayers and businesses, income, assets and transactions. It then matches its findings against the information the taxpayer has provided through their return. Discrepancies are flagged and could prompt a tax investigation.....Read more here