By Jonathan Davies
HMRC has said it has earned 60% more tax as a result of a crackdown on the "mass affluent" in 2014.
HMRC's Affluent Unit, which targets UK residents earning more than £150,000 a year or have £1m in wealth, raised £137.2m in tax in 2014, compared with £85.7m in 2013.
Law firm Pinsent Masons compiled the report using HMRC data.
The firm's head of litigation and compliance James Bullock said: "This surge in extra revenue from Affluent Unit tax investigations serves as a reminder that HMRC is widening its lines of inquiry.
"People who would just consider themselves moderately successful professionals and business people are now also coming under the scrutiny of HMRC's specialist units."
Treasury minister David Gauke said the higher tax revenues figures showed that the Affluent Unit cost tens of millions of pounds to set up was a success. "We are determined to give HMRC the powers and support that they need," he said.
Mr Gauke also said there was was a shift in public mood towards tax evasion and avoidance. "The public expect people to pay the right amount of tax under the law to help fund our services."
"HMRC are winning a lot of their court cases, and we are seeing that a lot of people are preparing to pay up rather than litigate for years."
But could HMRC collect more? Tax expert Richard Murphy, from Tax Research, thinks so.
He said: "HMRC is supposed to collect £167bn of income tax this year, of which at least a quarter will be from the top 1% of income earners.
"In that case, to collect just £127m as a result of investigations into this group when the official tax gap is £35bn suggests that much less attention is given to them than any other group."
He added: "The investigation success rate is way below anything that could be expected given that we know tax avoidance is mainly undertaken by the wealthiest.
"If these statistics prove anything it is that HMRC need many more resources to collect tax from those most likely to owe it."
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