Discovery Assessments and HMRC Penalty Appeals

Specialist advice on challenging HMRC discovery assessments and the lawful exercise of HMRC’s assessment powers

HMRC frequently relies on discovery assessments to assess historic tax said to be underpaid.

However, discovery assessments are only lawful where the statutory conditions for their use are satisfied.

In many cases, the critical issue is not merely the amount assessed, but whether HMRC had lawful power to make the assessment at all.

When Advice Is Commonly Required

Advice is commonly sought where:

  • HMRC has issued a discovery assessment for historic tax years

  • substantial assessments are issued shortly before expiry of statutory time limits

  • HMRC alleges careless or deliberate conduct to extend limitation periods

  • the taxpayer disputes whether a valid “discovery” was made

  • HMRC seeks to revisit matters previously known to it

  • procedural fairness or public law concerns arise in HMRC’s conduct

My Approach

I advise on discovery assessment disputes from both a tax litigation and public law perspective.

This includes advising on:

  • whether HMRC has lawfully satisfied the statutory requirements for a discovery assessment

  • whether HMRC is out of time to assess

  • whether allegations of deliberate conduct are sustainable

  • whether HMRC’s decision-making process has been procedurally unfair, irrational or otherwise unlawful

  • strategic appeal and judicial review options where HMRC has exceeded or misused its statutory powers

I have acted in complex litigation challenging HMRC’s use of discovery assessment powers, including cases involving sophisticated arguments concerning statutory construction, procedural fairness, legitimate expectation and abuse of power.

Clients and Sectors

My clients include:

  • property developers

  • entrepreneurs

  • owner-managed businesses

  • SMEs

  • high-net-worth individuals facing significant HMRC disputes

Why Specialist Advice Is Required

Discovery assessments often involve issues extending well beyond the underlying tax analysis.

They may require detailed consideration of:

  • statutory interpretation

  • limitation periods and extended time limits

  • HMRC internal decision-making and officer knowledge

  • evidential burdens concerning deliberate conduct

  • public law principles governing the exercise of statutory powers

A successful challenge may defeat the assessment in its entirety without the need to litigate the substantive tax position.

Fixed-fee strategic advice is available where appropriate for suitable matters.

Enquiries

Enquiries may be made using the contact form below.