What is the difference between COP8 and COP9 HMRC investigations?

COP8 is HMRC's civil investigation of fraud procedure where HMRC suspects serious tax fraud but proposes a civil settlement. COP9 is the most serious civil route, offering a Contractual Disclosure Facility (CDF) for full disclosure of deliberate fraud. Refusing COP9 or failing to make a complete disclosure significantly increases criminal investigation risk.

When should a tax expert witness be instructed in a COP8 or COP9 case?

Instruct before accepting or responding to a COP9 offer, and early in COP8 where HMRC's reconstruction methodology or technical tax analysis is disputed. Experts review financial records, challenge HMRC methodology, and support accurate disclosure positions.

HMRC Investigation Types: When Expert Evidence Helps

COP8 vs COP9: Key Differences

Feature	COP8	COP9 (CDF)
Trigger	Suspected serious tax fraud, civil route	HMRC suspects deliberate tax fraud, offers CDF
Disclosure	Negotiated civil settlement	Full disclosure of all deliberate fraud required
Criminal risk	Lower if cooperative civil settlement	High if CDF refused or disclosure incomplete
Expert role	Challenge HMRC methodology and quantify correct position	Review records before disclosure; support accurate CDF position

Code of Practice 8 (COP8)

COP8 (Code of Practice 8) is HMRC's civil investigation of fraud procedure, used where HMRC suspects serious tax fraud but proposes a civil rather than criminal settlement. Expert witnesses review HMRC's financial reconstruction, challenge the methodology where incorrect, and produce independent technical analysis of the correct tax position.

Code of Practice 9 (COP9)

COP9 (Code of Practice 9) is HMRC's most serious civil investigation procedure, the Contractual Disclosure Facility (CDF). HMRC offers the taxpayer civil settlement in exchange for full disclosure of all deliberate tax fraud. Refusal leads to criminal investigation. Tax expert witnesses assist by reviewing the financial records before disclosure, ensuring the disclosure is complete and accurate.

MTIC VAT Fraud Investigation

MTIC VAT fraud investigations involve HMRC tracing transaction chains to identify businesses connected to missing trader fraud and denying input tax where the knowledge test is met. The investigation procedure involves extensive document requests, transaction tracing, and assessment of the taxpayer's due diligence procedures.

Transfer Pricing Enquiry

HMRC transfer pricing enquiries investigate whether transactions between connected parties were priced at arm's length. The enquiry procedure involves requests for transfer pricing documentation, functional analysis, and comparables data. HMRC's transfer pricing yield increased dramatically in 2025 through more sophisticated enforcement and broader transaction targeting.

HMRC Criminal Investigation

HMRC pursues criminal investigation where the alleged fraud is serious, there is strong evidence, and prosecution is in the public interest, typically involving deliberate, substantial tax evasion. The HMRC Fraud Investigation Service leads criminal investigations, with tax expert witnesses producing CrPR Part 33 compliant expert reports challenging the prosecution's financial reconstruction.

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