RPC says requests went up by 19%, from 1,276 in 2015/16 to 1,507 in 2016/17. The firm says the increase follows the decision in 2015 to provide an extra £800m in funding to help meet a target of tripling the number of criminal investigations into tax crimes by 2020.

The orders, issued by HMRC’s criminal investigation directorate, compel professional services firms, such as accountants, to disclose confidential information relating to their clients who are suspected of tax fraud.

RPC says that firms issued with a production order can struggle to balance the need to provide HMRC with the requested documentation whilst at the same time ensuring they do not breach their duty of confidentiality owed to their clients. Firms can face criminal liability for failing to comply with a production order, but they also risk a legal claim from their clients if they provide too much information to HMRC.

Adam Craggs, partner at RPC, said: ‘The increase in production orders is a way of HMRC sending a clear message to those under investigation.

‘While it is quick and easy for HMRC to issue these orders, it is a huge burden on professional services firms. These investigations can take several years to complete and can cause serious business disruption to both suspects and their professional advisers.

‘The consequences for professional advisers who either fail to comply with a production order, or provide information to HMRC which they are not required to hand over can be very serious.’

Report by Pat Sweet