Peter Johnston


Peter is a partner in our Dispute Resolution team.  He advises domestic and international clients on commercial disputes, related advisory work and contentious regulatory matters.

Peter has extensive experience in corporate disputes, particularly shareholder disagreements and breach of warranty claims.  He advises professionals and their insurers in professional negligence claims and partnerships in various professions. He has wide-ranging experience in property disputes, statutory investigations and enforcement.

He has comprehensive experience in matters involving expedited case management in the Commercial Court as well as large-scale and complex discovery, data and information governance processes and related forensic reviews. Peter also leads large-scale projects associated with all legal aspects of regulatory inquiries.



  • Commercial and Regulatory Disputes
  • Privacy Litigation
  • Professional Indemnity
  • Shareholder Disagreements
  • Financial Services Disputes
  • Regulatory Investigations

Representative Matters

  • Representing a number of credit institutions in enforcement actions brought by the Central Bank in accordance with its administrative sanctions procedure.
  • Acting for an Irish company in relation to an investigation into alleged anti-competitive behaviour by the Competition and Consumer Protection Commission in the provision of tickets and the operation of ticketing services for live events.
  • Acting for Aer Lingus against the Dublin Airport Authority in respect of losses that Aer Lingus incurred due to failures of a baggage system at Dublin Airport.


Legal 500, 2021

Peter is a ‘Recommended Lawyer’.

Legal 500, 2020

Peter is a "highly skilled and tactically astute lawyer". 

Speaking Engagements & Teaching

Peter regularly lectures on the topic of litigation in the Law Society of Ireland.

Spoke at Mason Hayes & Curran's Property Litigation Seminar in 2019, 2018 and 2017.


Co-author of the Ireland chapter in the PLC Dispute Resolution Handbook/Arbitration Handbook 2010/2011

Co- author of the Ireland chapter in Thomas Reuters Practical Law Overview of Class/Collective Actions in Ireland 2020.

  • LinkedIn

Areas of Expertise

Dispute Resolution Commercial Disputes Insurance and Risk

Professional Memberships

The Law Society of Ireland

Committee member of the Commercial Litigation Association of Ireland


University College Dublin, BBLS (Int)

DePaul College of Law, Chicago , BBLS (Int)

Law Society of Ireland, Diploma in Commercial Litigation

Law Society of Ireland, Diploma in Commercial Law

Registered Patent Agent,