---
kind: "section"
citation: "19 U.S.C. § 4512"
title: "19"
title_heading: "Customs Duties"
number: "4512"
heading: "Relationship of the USMCA to United States and State law"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/19/4512"
units:
  - "Chapter 29 — United States–mexico–canada Agreement Implementation"
  - "Subchapter I — Approval of, and General Provisions Relating to, the Usmca"
---

# §4512. Relationship of the USMCA to United States and State law

- (a) **Relationship of USMCA to United States law—**
  - (1) **United States law to prevail in conflict—** No provision of the [USMCA](/usc/19/4502.md?p=9), nor the application of any such provision to any [person](/usc/19/1683.md?p=8) or circumstance, which is inconsistent with any law of the [United States](/usc/19/1683.md?p=9), shall have effect.
  - (2) **Construction—** Nothing in this Act shall be construed—
    - (A) to amend or modify any law of the [United States](/usc/19/1683.md?p=9), or
    - (B) to limit any authority conferred under any law of the [United States](/usc/19/1683.md?p=9),

    unless specifically provided for in this Act.

- (b) **Relationship of USMCA to State law—**
  - (1) **Legal challenge—** No [State](/usc/19/2577.md?p=2) law, or the application thereof, may be declared invalid as to any [person](/usc/19/1683.md?p=8) or circumstance on the ground that the provision or application is inconsistent with the [USMCA](/usc/19/4502.md?p=9), except in an action brought by the [United States](/usc/19/1683.md?p=9) for the purpose of declaring such law or application invalid.
  - (2) **Definition of State law—** For purposes of this subsection, the term “[State](/usc/19/2577.md?p=2) law” includes—
    - (A) any law of a political subdivision of a [State](/usc/19/2577.md?p=2); and
    - (B) any [State](/usc/19/2577.md?p=2) law regulating or taxing the business of insurance.
- (c) **Effect of USMCA with respect to private remedies—** No [person](/usc/19/1683.md?p=8) other than the [United States](/usc/19/1683.md?p=9)—
  - (1) shall have any cause of action or defense under the [USMCA](/usc/19/4502.md?p=9) or by virtue of congressional approval thereof; or
  - (2) may challenge, in any action brought under any provision of law, any action or inaction by any department, agency, or other instrumentality of the [United States](/usc/19/1683.md?p=9), any [State](/usc/19/2577.md?p=2), or any political subdivision of a [State](/usc/19/2577.md?p=2), on the ground that such action or inaction is inconsistent with the [USMCA](/usc/19/4502.md?p=9).

## Source credit

(Pub. L. 116–113, title I, § 102, Jan. 29, 2020, 134 Stat. 15.)

## Notes

### Editorial Notes

### References in Text

This Act, referred to in subsec. (a)(2), is Pub. L. 116–113, Jan. 29, 2020, 134 Stat. 11, known as the United States-Mexico-Canada Agreement Implementation Act. For complete classification of this Act to the Code, see Short Title note set out under section 4501 of this title and Tables.