Tax credits for out-of-state income
Comptroller of the Treasury of Maryland v. Brian Wynne, et ux.
In brief
The Supreme Court agreed with Maryland’s highest court that the state’s tax system violated the Constitution’s rule against discrimination in interstate commerce.
- Where it stands
- Decided
Decided 5-4 · May 18, 2015 · Opinion by Justice Alito
- What it’s about
- Maryland residents Brian Wynne and his wife challenged the state’s tax system, which taxed income earned in other states without fully crediting taxes paid there.
- Who it affects
- Maryland’s personal income-tax scheme was ruled unconstitutional because it discriminated against interstate commerce.
Summary: written with AI from the case record.
What it's about
The Supreme Court agreed with Maryland’s highest court (affirmed), ruling that the system violated the Constitution’s dormant Commerce Clause because it discriminated against interstate commerce.
Maryland taxed residents on income earned outside the state without fully crediting taxes they paid to other states.
Question presented
Does the dormant Commerce Clause of the Constitution prohibit states from taxing all the income of their residents by mandating a credit for taxes paid related to income earned in other states?
What the Court decided
Holding
Maryland’s personal income tax scheme violates the dormant Commerce Clause. 431 Md. 147, 64 A. 3d 453, affirmed.
- Result
- Affirmed
The Court's reasoning
The Court decided that Maryland’s tax scheme discriminated against interstate commerce, which the dormant Commerce Clause bars.
The vote
From the opinions
“The fundamental problem with our negative Commerce Clause cases is that the Constitution does not contain a negative Commerce Clause. It contains only a Commerce Clause.”
What's next
The Supreme Court has finished the case, and the Maryland court’s ruling remains in place.
Documents
Opinions
Docket activity
New analysis added
AI analysis generated: Impact Analysis
AI analysis generated: Opinion Summary
New analysis added
AI analysis generated: Case Briefing
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AI analysis generated: Decision Record
Case data updated: summary, question_presented, generation_metadata
Case data updated: question_presented, extraction_metadata
Opinion added: Wynne
More questions
- Why did Justice Ginsburg disagree?
- She argued that a state may tax all its residents’ income, including income earned outside the state.
Sources
Primary materials plus reporting. Best-effort analysis: this explainer relies on a mix of primary materials and trusted secondary sources. Official filings and opinions remain authoritative.