"James excels in every facet. His knowledge and expertise are matched by his thoughtful and attentive client service."
Chambers USA


James Casey is a partner in Mayer Brown’s Chicago office and leads Mayer Brown’s Private Client, Trusts & Estates practice. He has a wide‐ranging estates, trusts and foundations practice. He has significant experience in representing not‐for‐profit organizations, and in representing high net‐worth individuals and families in all aspects of estate planning.

With respect to not‐for‐profits, Jim provides advice in all matters relating to formation, administration, grant making, fundraising and planned‐giving, tax planning and compliance, and litigation. He is frequently called upon by not‐for‐profit boards and managers to address the most complex legal issues. With almost two decades of experience at Mayer Brown, he knows well the resources of Mayer Brown’s global platform, and is thereby well‐suited to bring a team‐oriented, multi‐disciplinary approach to solving these issues. Jim is experienced in working directly with regulators (including the Internal Revenue Service and state attorneys general) in matters relating to the ongoing tax qualification and regulatory compliance with respect to his not‐for‐profit clients. Clients he represents include public charities, private operating and non‐operating foundations, community foundations, university endowments, hospital endowments and corporate foundations.

With respect to estate planning, his practice includes the design and drafting of legal documents to achieve both tax and non‐tax motivated objectives. Among the estate planning instruments he prepares are wills, revocable trusts (living trusts), irrevocable trusts, dynasty or “perpetual” trusts (GST exempt trusts), grantor retained annuity trusts (GRATs), qualified personal residence trusts (QPRTs), charitable remainder trusts, and charitable lead trusts. Jim also assists clients with charitable gift agreements, premarital agreements, powers of attorney for property and for health care, and living wills.

Fiduciaries (executors and trustees) rely on Jim for all aspects of estate and trust administration, including probate administration, trust administration, preparation of state and Federal estate tax returns, preparation of accountings, and termination and distribution of estates and trusts. He also represents fiduciaries and individual clients in a variety of trust and estate litigation, including controversies over will and trust construction and alleged breaches of fiduciary responsibilities.

Before joining Mayer Brown in 2000, Jim practiced with two other law firms. Following law school graduation he served a judicial clerkship with Justice Anne M. Burke, Illinois Appellate Court, First Judicial District, Second Division. A Certified Public Accountant, Jim worked with a national accounting firm for three years prior to law school.

Jim is ranked in 2023 by Chambers USA’s High Net Worth Guide for Private Wealth Law – Illinois. Clients in Chambers USA state, "Jim's service to the family over many years has been invaluable. At every turn, he has been more than a match for the threats and concerns that periodically arise for any well-heeled entity" and he "is very smart and very good at service and communication and puts the clients' interests first." Also, "Clients value his 'smart and well-judged advice.'" Jim has been repeatedly recognized by Best Lawyers.


  • Anglais


The John Marshall Law School, JD, cum laude
Executive Editor, The John Marshall Law Review

Western Michigan University, BBA

Certified Public Accountant, Illinois

Inscription au Barreau


  • Michigan
  • Illinois


  • Chair, Ravinia Planned Giving Advisory Board
  • Member, WTTW‐11 and 98.7‐WFMT Planned Giving Advisory Committee; Committee Chair from 2007 through 2017
  • Member, Professional Advisory Committee of The Chicago Community Trust
  • Chicago Estate Planning Council
  • Chicago School of Violin Making, Former Board Member