Timothy P. Noonan & Noah S. Chase (Hodgson Russ LLP), Setting the Standard: A Major Development in Connecticut Domicile Cases, 121 Tax Notes State 531 (Aug. 17, 2026)

Over the years, we’ve spent a lot of time exploring the nuances of state tax residency and domicile issues in New York and other states. This is an area of state and local tax law that seems to be taking on an even greater focus, especially as taxpayers have become more mobile and states have become more aggressive, auditing more taxpayers.

A dull but important topic in this area is the standard of proof, because it dictates precisely how hard it is for taxpayers to win these cases. It’s a given in most states that to prove a change of residency from one state to another, a taxpayer not only bears the burden of proof to prove a change of domicile, but that burden is, typically, the high “clear and convincing” standard. In other words, a taxpayer won’t succeed without presenting clear and convincing evidence of a move — evidence that demonstrates a high probability of truth. This has led to myriad cases in which taxpayers, with arguably good facts in a residency case, still fell short of meeting their burden of proof.

In a recent development that has gone largely unnoticed, the Connecticut Supreme Court took aim at this clear and convincing standard. In Daniels v. Commissioner of Revenue Services, the court held, sua sponte, that Connecticut trial courts have been applying the wrong standard of proof to appeals from the commissioner’s determination of domicile for estate tax assessments. The decision is likely to cause shock waves in the residency arena, or at least in Connecticut residency cases. In this article, we examine what happened and how it could affect Connecticut audits and appeals.

All these principles are directly, if not purposefully, applicable to personal income tax determinations of domicile.

Thus, the idea that the court would disallow the use of a clear and convincing standard in domicile cases for estate tax purposes but allow it to be used in domicile cases for income tax purposes is silly. There should be no debate. In Connecticut domicile cases, taxpayers will have to prove their move only by a preponderance of evidence. The clear and convincing standard is effectively dead.