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Self-Assessment Tax Investigations – COP 11

If you are suspected of reporting less money on your self-assessment tax return than you should have, Her Majesty’s Revenue and Customs (HMRC) can conduct a COP 11 investigation against you. If you are subject to an HMRC investigation, it is in your best interests to get in touch with a solicitor at your earliest convenience and we will deal with your case throughout the entire legal process. We are available to represent you anywhere within the country and can instruct specialist tax advisors and forensic accountants if needed.

Free Initial Telephone Consultation

Our highly skilled Fraud team are here to take the worry off your hands. We can provide an initial telephone consultation to see how we can assist in your case. Please call us on 0808 168 5550 or email

COP 11 Investigation Procedure

If HMRC believe that the figures for your tax returns do not add up, then this will usually be carried out under Code of Practice 11 by HMRC. COP 11 investigations are carried out in relation to income tax returns by Local Compliance Offices, and they can moderate up to the last 20 years of your tax activities under the Taxes Management Act 1970. If you are found to have committed a serious fraud, a COP 9 or criminal investigation may take place.
If there is clear evidence against you that you have committed tax fraud, you can be ordered to pay back all the money you owe with additional fines that HMRC feel are necessary. If it is serious enough, you could even face a custodial sentence.       

Can you do anything to reduce your punishment?

HMRC may enforce penalties on you as punishment for filing incorrect self-assessment tax returns and will take certain factors into account such as the seriousness of the fraud. If you are faced with a fine, you could pay up to 100% of the tax liability but it can be reduced if depending on the level of disclosure, cooperation and the seriousness of the allegation. Whilst HMRC issues guidance for the percentages of reduction in penalties, this process is inevitably not an exact science and requires careful analysis. By way of example, If you choose to make a full disclosure to HMRC early into the investigation, you may be given a reduction from a penalty in the region of 20%.

Who are HM Revenue & Customs (HMRC)?

Her Majesty’s Revenue and Customs (HMRC) is a non-ministerial department of the UK government that oversees various financial responsibilities, most notably the collection of taxes. The department is responsible for the administration and collection of various taxes including income tax and corporation tax while also helping families and individuals with targeted financial support such as the distributions of tax credits including child benefits. Their overall aim is to therefore ensure that we are taxed the right amount and to make it as difficult as possible for people to take advantage of the tax system.
HMRC also have their own inland detention officers who have the legal authority of arrest, entry, search and detention. Their main power is to arrest anyone who has committed, or are suspected of committing an offence. Their prosecution cases may take place with the police or the Crown Prosecution Service.

How we can help

If you have been accused of tax fraud, our Tax Defence Solicitors are available to argue your case and advise you throughout the entire process of the trial. We therefore promise to:

•    Advise you throughout the entire process
•    Represent you in an initial interview with the HMRC
•    Prepare and collate all required documents for the HMRC
•    Represent you in court if necessary
•    Take the worry off your hands
•    Argue your case
•    Prepare an appeal if necessary

Given the broad area of law surrounding tax fraud, we will ensure to deal with your case by finding all of the facts and circumstances.

Our team are highly ranked in the Legal 500 and Chambers and Partners guides. We have extensive experience in successfully defending businesses and individuals accused of fraud.

Why Choose Us?

At Cartwright King, our solicitors understand the stress and worry being accused of tax fraud can cause and the potential long term consequences that can affect you, your business and your family life. We are available to support you throughout the entire process, explain the likely outcomes and fight on your behalf.

How to make contact

If you require any legal advice or if you would like a no obligation, free initial telephone discussion, then please call us on 0808 168 5550. Alternatively you can email the Fraud team on and we’ll get back to you as soon as possible.

Our Tax Defence Solicitors can provide advice across the country and are happy to meet at a time and location that suits you. We also have a network of offices in BirminghamBedfordDerbyLeedsLeicesterLondon TempleLutonManchesterMiddlesbroughNorthamptonNottinghamOxfordSheffield.

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