Janna McGuigan

Janna is an experienced advocate practising in civil and commercial litigation. She has particular expertise in disputes concerning trusts, estates, contract and equity and is regularly engaged to conduct high-profile independent inquiries.
Janna is a results-focused barrister. She provides pragmatic and commercially realistic advice in a wide range of general civil and commercial disputes, including contract and tort matters, governance issues and in complex litigation. She assists high net worth families and trustees with advisory opinions and compliance advice. In addition to her core specialisms in trust and estate disputes, Janna has a particular interest in contract, professional negligence and judicial review.

She has appeared at all levels of the New Zealand courts, and is instructed as lead counsel and counsel assisting the High Court. She also appears as junior counsel with some of New Zealand’s leading silks.

In addition to her work as an advocate, Janna regularly presents at professional seminars/conferences and is actively involved in law reform, including as a former member of the New Zealand Law Society Law Reform Committee and past president of the Auckland Women Lawyers’ Association.

Prior to joining the independent bar in 2016, Janna worked at Wilson Harle (Auckland) and at Russell McVeagh (Wellington). She holds a Masters of Law from the University of Michigan, where she was a Grotius Fellow in 2010-2011, and a BA / LLB (First Class Hons) from the University of Canterbury (2007). Following graduation, Janna spent two years as a Judge’s Clerk to the Rt Hon Sir Andrew Tipping at the Supreme Court of New Zealand.

She has chambers in Christchurch and Auckland and accepts instructions from around the country.


  • Company
  • Competition and Fair Trading
  • Contract, Civil and Commercial Disputes
  • Insurance
  • Judicial Review and Public Law
  • Trusts
  • Wills and Estates

Case Highlights

Smalley v Williamson [2023] NZCA 174
Successfully acted for remaining shareholders to uphold an order for summary judgment to enforce an expert determination of the value of company shares, including obtaining an order that the Registrar of the High Court sign share transfer documents on behalf of the exiting shareholder.

Parry Field Lawyers Ltd v Disputes Tribunal at Christchurch [2023] NZHC 1829
Appointed as amicus curiae (independent counsel appointed to assist the Court) in a judicial review of the Disputes Tribunal’s decision (upheld on appeal) that it had jurisdiction to hear claims in relation to solicitor fees that have been the subject of determination by a New Zealand Law Society Standards Committee.

Client Trustee Services Ltd v Khodaverdi [2023] NZHC 1772
Successfully acted for professional trustee seeking directions from the Court in relation to defence of related litigation and for removal of trustee.

McLaughlin v McLaughlin [2023] NZCA 473
Acted for interested party (beneficiary) in an appeal concerning scope of trustee obligations and conflicts of interest.

Glass v Glass [2022] NZHC 3233
Acted for executor in a hearing to determine whether leave ought to be granted to bring proceedings under s 88 of the Property (Relationships) Act 1976 to challenge trust settlements and other relationship property assets.

Newton v Family Court at Auckland [2022] NZSC 92; [2022] NZSC 112; [2022] NZCA 207; DN & LN v Family Court at Auckland [2020] NZHC 3165
Acted for parents on judicial review of Family Court processes / decisions and the role of lawyer for children, including obtaining an interim stay from the Supreme Court of the underlying Family Court proceeding.

Lambie Trustee Ltd v Addleman [2021] NZSC 54
Acted for the trustee in the leading Supreme Court authority on disclosure of legal advice by trustees to beneficiaries.

McCallum v McCallum [2021] NZCA 237
Successfully acted for the plaintiff beneficiaries in  the leading Court of Appeal authority on applications by trustees for access to trust funds to defend litigation.

Clarke v Clements [2021] NZHC 2716
Acting for an executor to successfully resist a mutual wills claim.

IAG v Evans [2020] NZHC 1326
Appearing as amicus curiae (independent counsel appointed to assist the Court) on an application by an insurer to refer a question of law (contract interpretation) to the High Court from the Canterbury Earthquakes Insurance Tribunal.


New Zealand Bar Association
New Zealand Law Society
Canterbury Women Lawyers’ Association