Tax investigations and controversy

Our international tax investigation team is made up of highly experienced professionals in the UK, US and Asia who have spent decades advising on complex and high-stakes cases.

Having acted in many high-profile cases we know that a ‘one size fits all’ approach does not work and will carefully review your situation and develop a tailored strategy. Our reputation is second to none, with Chambers & Partners describing us as ‘a very well-respected, high-class operation’.

We can all agree that tax is now a more contentious issue than ever before, with the press naming and shaming accused tax avoiders as well as evaders and government giving treasury and regulators greater powers to investigate, penalize and prosecute individuals and businesses. We are frequently consulted by people who have inadvertently signed up to a tax ‘scheme’ of some kind and are currently representing individuals and companies caught up in film schemes as well as high profile individuals in the work of international football.

We also help those who wish to make a voluntary disclosure of unpaid taxes, ensuring that the process is handled confidentially and with protection from criminal investigation wherever possible. Maurice Martin, of counsel in London focusing on UK tax investigations, says ‘it is always better to approach the authorities than to wait for a knock on the door’.

In the UK, we offer robust advice on civil and criminal tax fraud investigations and litigation by the tax authorities. Our team includes lawyers who have worked within the tax authorities and have valuable insight into their methods and approach. One of our lawyers, special counsel in London, Tessa Lorimer, is a former tax fraud prosecutor who specializes in representing companies and individuals subject to investigations and litigation. In a recent case, she successfully advised on a £5 million fraud involving accountants who were acting as trustees and administrators of pension schemes that were being investigated by HMRC, FSA and the Pension Regulator. ‘HMRC has more punitive powers than ever,’ she says. ‘Anyone with concerns about their tax position should act now.’

In the US, we recently persuaded the IRS and the State of Connecticut not to criminally prosecute a client who had failed to file tax returns for eight years, arguing the mitigating factors of emotional turmoil and the economic downturn.

In Singapore, Withers KhattarWong LLP allows clients to access the best-in-class tax investigation and controversy expertise through our Singaporean Counsel. In 2017, our tax partner, Joanna Yap successfully represented our client in relation to the ‘additional buyer’s stamp duty regime’ which the High Court ruled does not apply to residential property purchased by a charity. The landmark decision has wide-ranging impact to charities and the non-profit sector in Singapore.

Any controversy related to tax can be damaging, regardless of whether or not there has been any wrongdoing. It is for this reason we offer the services of our reputation management team, who can help to manage coverage of cases where there is a media interest.

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2022 Chambers HNW, Tax: Private client, Band 1

2022 Chambers UK, leading firm in tax: contentious fraud

Ranked for tax: contentious trust

Ranked in Band 1 for private client for the last 16 years

Ranked in top tier for personal tax, trust and probate

UK top 25 private client law firm 2017


I was fortunate to have the support of a great team of highly qualified professionals who made feel me that I was in the right hands, who acted promptly and decisively in addressing my needs and concerns and who maintained a warm personal touch during our business relationship. I will always be grateful to them for the successful completion of my case.

Ernesto Santos

Today’s increasingly complex tax labyrinth of local, state, federal, and international compliance requires unique skills and competence. Shannon [Smith Retzke] and her team have both the savvy and experience but more importantly the sophistication to negotiate favorable outcomes.

Corbin Wood, COO - Snow Companies


How the team can help


Domicile investigation

We frequently advise UK residents who are non-domiciled, where they are under investigation by HMRC. This can the take the form of inquiries into their residence as well as their claim to be no-domiciled and also where challenged are made into specific remittances. It is a complex area, where we work closely with our wealth planning colleagues. We have had several notable success in this area in the past few years.

Senior professional involved in tax fraud

Our team in London is advising a senior professional in relation to tax fraud, taking him through a Contractual Disclosure Facility ("CDF"). This type of voluntary disclosure that allows individuals to own up to tax fraud, in return for a promise from HMRC not to commence a criminal investigation. He was extremely concerned about the process and subsequent investigation, but our team helped to simply and speed up the process, managing communications with HMRC and allowing the client to move on with his life.

A US citizen who had not filed tax returns

Our New Haven office persuaded the IRS and the state of Connecticut not to criminally prosecute a client who had failed to file individual, withholding, sales and corporate tax returns for eight years as a result of the economic downturn and some personal emotional turmoil.

London banker facing bankruptcy proceedings

We acted for an investment banker in London who was facing bankruptcy proceedings as a result of a petition from HMRC for non-payment of tax. The non-payment was related to the sale of bank shares where she previously worked, which would have had a significant impact on her livelihood. We negotiated with HMRC on her behalf, saving her from bankruptcy proceedings and without adverse publicity.

Managing Canadian-US reporting obligations

A Canadian-US family living on both sides of the US-Canadian border asked us to assist with US reporting deficiencies (FBAR, FATCA, income tax returns, entity reporting, etc), where the potential IRS penalties well exceeded USD $1 million. We successfully negotiated full penalty waiver on all missed reporting forms for all impacted family members.

High-profile individuals in football

We are acting for a number of figures in the international football industry in relation to a Code of Practice 8 (COP 8) investigation. Our clients were missold investment schemes that amounted to tax avoidance, and we are dealing with HMRC on their behalf and negotiating a settlement with their negligent advisers.

Negotiating voluntary disclosures

Assisting clients in negotiating disclosures under the Liechtenstein Disclosure Facility (LDF) for clients with complex offshore structures - sometimes working in tandem with US qualified colleagues when the client also needed to make a voluntary disclosure in the US.

Pension fraud

Tessa Lorimer, a member of our tax investigation team in London, advised on a £5 million pension fraud involving accountants who were acting as trustees and administrators of Pension schemes which were investigated by HMRC, FSA and the Pension Regulator.

Canadian and Swiss accounts tax case

We successfully abated over USD $2.8 million in potential penalties for a Canadian family living in America, advising on an IRS defense action with respect to Canadian and Swiss accounts.

Colombian family IRS case

We represented a Colombian family with interests in Colombia and Brazil, which had been briefly stationed in the United States, with a delicate IRS matter. We assisted the family in negotiating a penalty abatement of upwards of US$1.6 million in potential penalties, and all of the IRS meetings and negotiations were addressed without clients needing to be physically present in the United States.

US tax compliance for Brazilian entrepreneur

We investigated the circumstances of a client who was a Brazilian entrepreneur investing in the United States. We determined that he had inherited United States citizenship from his parents but had never filed US income tax returns or reporting forms. We quickly and efficiently addressed the noncompliance by entering him into the IRS offshore streamlined program.

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