The penalties would apply to enablers of defeated tax avoidance and, where liability is established, be "equal to the amount of consideration either received or receivable by them for enabling those arrangements", HMRC said.
HMRC's draft guidance on penalties for enablers of defeated tax avoidance (61-page / 877KB PDF) is designed to complement provisions contained in the second Finance Bill 2017, which is currently making its way through parliament. The proposals set out how those provisions interact with the existing General Anti-Abuse Rule (GAAR).
HMRC said: "An enabler is any person who is responsible, to any extent, for the design, marketing or otherwise facilitating another person to enter into abusive tax arrangements. When such arrangements are defeated in court or at the tribunal, or are otherwise counteracted, each person who enabled those arrangements may be liable to a penalty."
According to the proposed new guidance, tax avoidance measures can be said to be defeated in a variety of circumstances, including where the prospective advantages are counteracted by steps taken by the taxpayer themselves. In other cases, HMRC might make assessments, or apply counteractions, to negate the prospective improvements in a company's tax position which could expose enablers of those defeated tax avoidance schemes to liability.
"In its efforts to tackle tax avoidance, HMRC has increasingly turned its sights on the advisers that created or promoted arrangements, and these measures show its clear intent in this area," tax expert Paul Noble of Pinsent Masons, the law firm behind Out-Law.com, said. "Their thinking is that by turning off the supply of schemes, taxpayers will not be tempted to become involved anymore."
The draft guidance was published as the Tax Faculty of the Institute of Chartered Accountants in England and Wales (ICAEW) warned against a planned crackdown on the beneficiaries of employment benefit trusts (EBTs) and other disguised remuneration (DR) schemes.
An EBT is a legal structure which is usually set up by an employer for the benefit of its employees and directors or their family members. EBTs can be used by companies for many purposes, including to support their employee share plans and executive long-term incentives. However, they were also historically used by many businesses, particularly hedge funds and banks that used them to manage tax payments on bonuses, before many of the tax advantages of the structure were removed by new rules on disguised remuneration in the 2011 Finance Act.
HMRC has been targeting the abusive use of these structures for a number of years, as it is its view that they artificially lower income tax and national insurance contributions that would otherwise be paid on employee remuneration.
The ICAEW said, however, that it was against proposed new legislation which would apply new charges on outstanding loans from DR schemes.
"The exchequer need to recover tax lost needs to be balanced with legitimate expectations, and introducing a charge on transactions entered into up to 20 years ago which potentially could result in taxpayers becoming insolvent … may not only leave the government vulnerable to challenge under human rights law but actually reduce the tax yield," it said.
The ICAEW said that workers such as nurses, teachers, IT workers and cleaners are among those who were potentially misled into participating in a DR scheme.
"Some people using DR schemes knew exactly what they were doing and were deliberately avoiding tax: they deserve little or no sympathy," the ICAEW said. "In fact HMRC should have acted far sooner against these schemes. However, not all taxpayers are in this position. Unfortunately, many others were misled about the arrangements and would not have appreciated what they were doing: in their case, while their position needs to be regularised and tax paid, we think that they should not be so heavily penalised."
The ICAEW raised its concerns in a submission to the House of Commons Public Bill Committee.