Jonathan Leinheardt

Jonathan Leinheardt has practiced law since 1992. His practice focuses on probate litigation, trust and estate litigation, trust and estate administration, protective proceedings, fiduciary disputes, elder law, civil litigation, and domestic relations.

Jonathan began his legal career as an Assistant District Attorney in the Queens County District Attorney’s Office in New York City. After six years as a prosecutor, he entered private practice in New York, where guardianship and protective proceedings became a significant part of his work. He has continued that focus in Colorado since 2003.

Jonathan represents clients in contested and uncontested guardianship and conservatorship matters, probate disputes, trust disputes, fiduciary litigation, estate administration disputes, and related elder law matters. These cases often involve capacity issues, family conflict, fiduciary authority, accountings, removal issues, care decisions, financial management, and court supervision.

Jonathan regularly represents professional and non-professional fiduciaries, including guardians, conservators, trustees, personal representatives, and agents acting under powers of attorney. He has also served as respondent’s counsel in protective proceedings, as a Court Evaluator in New York City, as a property guardian, and as trustee of supplemental needs trusts. That experience gives him practical insight into the duties and challenges fiduciaries face.

Jonathan believes many probate, trust, guardianship, conservatorship, and family disputes should be resolved through careful negotiation or mediation when a fair resolution is possible. He works with clients to evaluate the costs, risks, benefits, and likely outcomes of litigation so they can make informed decisions. When a case cannot be settled because the other side is unreasonable, unfair, or unwilling to reach a workable resolution, Jonathan is prepared to advocate firmly for his client and ask the court to resolve the dispute.