Meet Our Team

Our team delivers high-quality and transparent legal representation devoted to achieving your best outcome.

We offer services in both official languages.

Adam T Castonguay

Ronald V. TrebbLeighton T. RoslynArt Lambert

Jacob PelletierStephanie E. McMahon

Looking for a member of our Support Team?

Adam T Castonguay

B.A. Hons., J.D.

Partner *

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Adam is a graduate of the Bora Laskin Faculty of Law at Lakehead University where he earned his Juris Doctor with first class standing, and Laurentian University where he obtained a Bachelor of Arts in Law and Justice with honours, cum laude. He also holds a Certificate in Construction Law from Osgoode Hall Law School Professional Development. He practices real estate, Wills and estates, corporate and commercial law, as well as construction law and civil litigation.

You can trust Adam to provide expert advice in real estate transactions, including those involving commercial properties and multi-family or income properties. He can also assist with refinancing, liens, property development, boundaries or access disputes, and more.

Adam also represents clients in a variety of litigation matters such as construction liens, shareholder disputes and breach of contract. Wherever possible, he will explore resolutions without the need to resort to the courts.

Working with established businesses and budding entrepreneurs, Adam advises on corporate and commercial matters including incorporating and corporate reorganizing, asset and share purchasing, and commercial leasing.

He can help you plan for the future with a well drafted Will and Estate plan, and helps trustees through the often difficult task of administering an estate.

Adam’s client-centric approach makes him a great addition to your team, where he will work in collaboration with everyone at Conroy Scott LLP to meet all your legal needs.

Practice Areas:

  • Real Estate Law
  • Property Law
  • Construction Law and Construction Liens
  • Civil Litigation
  • Corporate and Commercial Law
  • Wills and Estates

* Through Professional Corporations

Ronald V. Trebb

B.Sc., LL.B.

Associate Lawyer

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Ronald V. Trebb is a graduate of both Laurentian University (1975) where he obtained a B.Sc (in physics), and also the University of Windsor (also 1975) where he obtained his Bachelor of Laws degree (LL.B). He was called to the Ontario Bar in 1977 and has practiced as a partner of the firm since 1978.

Ron’s present practice focuses primarily upon various aspects of corporate/commercial law. He provides services related to the incorporation, organization, re-organization, amalgamation and dissolution of corporation. He also advises his clients with respect to asset purchase and share purchase type transactions, franchising and licensing arrangements, shareholder agreements and other corporate governance issues His practice also encompasses the provision of necessary professional services to a number of Professional Corporations incorporated for physicians, dentists, barristers and solicitors and other professionals.

In addition, for the better part of 35 years Ron has been active as both a Barrister and Solicitor in all aspects of commercial and residential real estate law. As a barrister, he has been involved in numerous litigious matters between vendors and purchasers, contractors and sub-contractors, principals and agents, and builders and their customers. He has acted for both lenders and borrowers in foreclosure actions, powers of sale proceedings, and other mortgage/security enforcement proceedings. As a solicitor, he has represented clients in numerous major asset acquisitions, asset dispositions, re-financing, leasing, and property development transactions.

Ron has given special lectures at Laurentian University and Cambrian College in Sudbury. He was previously accredited and taught Real Estate Law to real estate agents seeking provincial certification through the Ontario Real Estate Association in various locations throughout Ontario.

Practice Areas

  • Corporate & Commercial Law
  • Wills & Estates
  • Real Estate

Leighton T. Roslyn

B.A. Hons, LL.B.

Associate Lawyer

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Leighton T. Roslyn has been associated with the firm since 2001.

He has over 40 years of experience in corporate and commercial transactions, real estate, wills & estates, powers of attorney, as well as the law related to charities and non-profit organizations.

He also has a depth of experience in litigation matters involving insurance work, contract disputes, construction liens and construction law, real estate disputes, commercial and business law disputes and general Court related issues.

Non-profit and charitable organizations are a special interest.

Practice Areas

  • Litigation General & Corporate/Commercial
  • Corporate/Commercial Transactions
  • Real Estate
  • Wills & Estates

Art Lambert

LLM

Associate Lawyer

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Art Lambert is a licensed lawyer in both Ukraine and Ontario and was the first recipient of a Certificate of Foreign Legal Consultant in Ukrainian Law from the Law Society of Ontario. Holding LL.M. degrees in both Civil Law and Common Law, Art has a deep understanding of both legal systems and extensive experience handling complex estate and family matters, including multinational cases.

In addition to Canada, his practice has involved high-stakes family and estate proceedings across multiple jurisdictions, working alongside leading firms in the UK, Monaco, France, Russia, Ukraine, Panama, Canada, and the USA.

In addition to his expertise in estate and family law, Art specializes in Immigration Law and Non-Profit & Charitable Law in Ontario.

Beyond his legal practice, Art is deeply committed to charitable and non-profit work, actively contributing to the betterment of society by supporting organizations dedicated to humanitarian aid, community development, and social justice. He is a valuable member of the Ukrainian community, providing legal guidance and advocacy for individuals and organizations in need.

Art’s intellectual pursuits extend beyond law—he holds a Master’s degree in Theology, reflecting his deep interest in philosophy, ethics, and religious studies. His interdisciplinary background allows him to approach legal and societal issues with a broad and insightful perspective.

Fluent in English, Ukrainian, and Russian, Art effectively serves a diverse clientele, offering legal expertise that bridges multiple cultures and jurisdictions

Practice Areas

  • Wills & Estates
  • Estate Litigation
  • Family Law
  • Immigration Law

Jacob Pelletier

B.A. Hons, J.D., LLL

Associate Lawyer

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Jacob is a graduate of the University of Ottawa Faculty of Law where he earned his Juris Doctor and Licentiate in Law concurrently, and Laurentian University where he obtained a Bachelor of Arts (Honours) in Law and Justice (Droit et justice). He also holds a Diploma in Police Foundations (Techniques des services policiers) from Collège Boréal.

He is a dedicated worker with years of experience in the private sector and trades predating his law studies. He is committed to mastering his various fields of practice and maintaining strong relationships with his clients.

He is a member of Serpent River First Nation and is dedicated to advancing indigenous causes.

He is a francophone and is pleased to provide services in both French and English.

Outside of law, Jacob enjoys playing music on his various instruments, and reading.

Practice Areas

  • Civil and Commercial Litigation
  • Family Law
  • Administrative Law
  • Indigenous Legal Issues

Stephanie E. McMahon

BSW, MSW, JD

Associate Lawyer

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Stephanie was born and raised in Sudbury, Ontario. She obtained a Bachelor of Social Work and a Master of Social Work from Laurentian University followed by her Juris Doctor degree from the University of Moncton.

During her law studies, she worked as a social worker counselling individuals, couples and families in the private sector. Following the completion of her studies, Stephanie articled with a local civil litigation law firm.

Qualified as a social worker and lawyer, with the respective skills of both professions, Stephanie is a strong compassionate advocate who thinks critically to address her client’s legal needs.

She is dedicated to her community and proud to establish her career in Northern Ontario.

Stephanie practices civil litigation, real estate, wills and estates, as well as immigration law.

Stephanie is bilingual and is pleased to provide services in both English and French.

Practice Areas

  • Civil Litigation
  • Wills and Estates
  • Real Estate
  • Immigration Law

Our Support Team

  • Carolyn Baril
  • Wills & Estates Law Clerk
  • email
  • Donna Caldwell
  • Corporate Law Clerk
  • email
  • Receptionist
  • Receptionist
  • email
  • Michelle Lefebvre
  • Real Estate and Administrative Clerk
  • email
  • Dorothy Machum
  • Chief Administrative Officer
  • email

Get in touch with us.

Our office is located at 164 Elm Street, Sudbury, ON P3C 1T7
Closed for lunch: 12:00 – 1:00 p.m.

Telephone:705.674.6441 Fax:705.673.9567