Contentious Tax

Our Contentious Tax team consists of tax advisors, chartered accountants, barristers and solicitors who work extensively in the tax controversy area. We act for individuals and corporates and assist our clients in resolving contentious tax matters before any court proceedings commence.

Our Contentious Tax service offering includes:

  • confidential reviews of tax filing positions taken and legacy tax matters;
  • advising on voluntary tax disclosures and tax settlements with tax authorities;
  • advocating on behalf of and representing clients at Tax Appeals Commission and High Court levels;
  • provision of expert witness tax reports;
  • tax risk management; 
  • tax warranty and tax indemnity claims;
  • assisting clients prior to and during tax investigations and audits; and
  • assisting with mutual assistance procedures (MAPs).

We concentrate on tax law and therefore have no accounting, audit or attest issues. We can therefore focus entirely on advising and supporting clients to adopt best practices, become more cost-efficient and reduce the burden that tax issues bring.

Click on the image below to download our Contentious Tax Brochure.

Contentious Tax













Our Contentious Tax team is composed of tax advisors (AITI/CTA), chartered accountants, barristers and solicitors. The team has gained considerable experience in dealing with Revenue audits and investigations, MAPs, and settlement negotiations with tax authorities. We have also acted as expert witnesses for taxpayers and foreign tax authorities in complex tax appeal cases.

Concerning tax litigation we have, in the past, advocated on behalf of and represented clients at Appeal Commissioner/Tax Appeals Commission, Circuit Court and High Court levels on matters relating to, inter alia, DIRT, income tax, capital gains tax, stamp duty, VRT, corporation tax, VAT and international tax matters. 


What To Expect When You Are Legitimately Expecting

On 3 June 2020 Perrigo opened its case in the High Court in a bid to quash one of the most contentious tax bills levied on a company in Ireland. This article considers the legal concept of legitimate expectation and the thresholds that Perrigo may have to meet to succeed in its case to have the tax bill reversed.

Time to Abolish the Close Company Surcharge for Professional Service Companies

Is it time, from a policy perspective, to abolish the close company surcharge for professional service companies?

View all


  • William Fry's Tax team have been described as "professional, well informed and forward thinking" as well as being a "responsive and partner-led tax practice issuing practical advice." One client notes that the team has an abundance of "knowledge, experience, professionalism and the ability to apply lateral thinking and multi solutions." Another client adds that they have "an excellent range of tax knowledge both locally and internationally." They are very "responsive and helpful, and we fully trust the advice that we receive."  Legal 500 2020
  • There's a real broadness, a client states "You can talk to one person who has a legal, tax and international perspective all in one".  Other sources appreciate the client-centric service provided by team members: "We've got a great relationship with the team and we find them to be very effective. They really demonstrate their commitment to client service". ​Chamber Europe 2019  
  • "William Fry's commitment to client service is excellent", says one source, who also praises "their real breadth of knowledge and willingness to allocate the people required when there is a need for a quick turnaround." Another reports that the "technical depth, exposure and experience of the senior team set them apart." Chambers Europe 2018
  • "Sources assert that "from a technical perspective they are clear and direct." Interviewees also value the team's "responsiveness to client needs and commercial awareness." Chambers Europe 2017
  • William Fry’s practice includes Sonya Manzor, who ‘devises well-thought-out tax strategies’ for clients such as King Digital Entertainment. International tax specialist Shane Wallace recently handled various real estate tax structuring and transfer pricing issues. Legal 500 EMEA 2017
  • "The firm is very responsive and has great resources, including access to a global network of tax advisers, which benefits us internationally and is a fantastic asset. The firm's ability to provide both legal and tax advice really ensures everything fits together." Chambers Europe 2016
  • Martin Phelan leads a ‘highly professional’ team at William Fry. It advised the Department of Finance on the potential capital restructuring and sale of its 99% investment in Allied Irish Bank, and also assisted IAG and EirGen Pharma. The group also has a significant private client practice and notable property expertise. . Legal 500 EMEA 2016
  • "Martin Phelan's controversy practice is at the forefront of domestic contentious tax work and boasts an enviable client list." Who's Who Legal - Corporate Tax 2015 


Martin Phelan

  • According to  Legal 500 2020, "Martin Phelan is the top tax adviser in Ireland. Martin’s straight-talking, honest approach ensures that he is a go-to individual for any advice. Martin is an incredible resource." Another client adds that he is a "stand out Partner" and one of their " most valued business partners." 
  • Martin is described by market commentators as "technically superb and grounded in the basics."  Chambers Europe 2020
  • Martin is a highly experienced tax consultant who is best known for his expertise in international tax. "He's very bright," explains one satisfied client, elaborating: "It's his pragmatic solutions and ability to look beyond the immediate problems, even to give warnings ahead of time. We are able to run things by him and he's very accessible, which we find very helpful." Chambers Europe 2019
  • Martin receives praise from his clients for "ensuring a blend of a technical and practical approach which is very digestible to the client and is easy to implement as a result." He is well known in the market for his international tax expertise. Chambers Europe 2018 
  • Martin Phelan International tax specialist Martin Phelan is described as a "top guy" and "very switched-on." Chambers Europe 2017

Brian Duffy

  • According to Legal 500 2020, Brian is "commercial and responsive".
  • Brian has been listed as one of Ireland's 'Tax Controversy Leaders' by the International Tax Review in 2015, 2016, 2017, 2018 and 2019.
  • Legal 500 2016 states that Brian is "recommended".

Key Contacts

Brian Duffy Partner

Martin Phelan Tax Partner with William Fry Tax Advisors Ltd

Fergus Doorly Partner

View All