U.S. Chamber Of Commerce Amicus Brief Urges Tenth Circuit To Reject Presumption Against Preemption In Colorado DIDMCA Case

The en banc Tenth Circuit continues to receive substantial support for affirming the district court’s decision in National Association of Industrial Bankers v. Weiser, the closely watched case addressing the scope of the opt-out provision in Section 525 of the Depository Institutions Deregulation and Monetary Control Act’s (“DIDMCA”), which empowers a state to opt out of the interest rate provisions in Section 521 of DIDMCA with respect to “loans made in such State.”

On June 4, 2026, the Chamber of Commerce of the United States of America filed an amicus brief supporting the plaintiffs-appellees and urging the en banc court to affirm the district court’s preliminary injunction against enforcement of the Colorado opt out statute. Unlike several other amicus briefs that have emphasized the practical consequences of the panel decision for interstate lending and credit availability, the Chamber’s brief focuses principally on federal preemption doctrine and argues that the panel majority’s analysis was fundamentally flawed because it relied on a presumption against preemption when interpreting the express preemption provision in Section 521 of DIDMCA.

We recently blogged about an amicus brief we submitted on behalf of a consortium of national and state trade associations of financial institutions in the same case. Our amicus brief describes the issue pending before the Tenth Circuit and the status of it.

The Chamber’s Core Argument: No Presumption Against Preemption Applies

The Chamber emphasizes that Section 521 of DIDMCA contains an explicit preemption provision that should be interpreted according to its plain language without any judicial thumb on the scale favoring state authority.

The brief points to DIDMCA’s operative language, which provides that a state-chartered, FDIC-insured bank may charge interest at the rate permitted by its home state law “[n]otwithstanding any State constitution or statute,” and that conflicting state laws “are hereby preempted” for purposes of the statute. According to the Chamber, Congress could hardly have spoken more clearly.

The Chamber argues that the panel majority nevertheless began its analysis with the presumption that federal law should not be read to displace state law absent a “clear and manifest” congressional purpose. In the Chamber’s view, that approach improperly influenced the panel’s interpretation of DIDMCA’s opt-out provision and led it to adopt an unduly narrow reading of the statute.

A Broader Attack on the Presumption Against Preemption

The most notable aspect of the Chamber’s brief is its extensive criticism of the presumption against preemption itself.

The Chamber argues that the presumption lacks support in:

• The text of the Supremacy Clause;
• The historical understanding of federal supremacy at the time of the Founding;
• The Constitution’s structural allocation of authority between Congress and the courts.

The brief relies heavily on scholarship and Supreme Court opinions questioning whether courts should employ a special rule that disfavors preemption. According to the Chamber, the Supremacy Clause directs courts to apply valid federal law as supreme over conflicting state law and does not require Congress to satisfy any heightened burden before federal law displaces state regulation.

The Chamber further argues that the presumption improperly interferes with Congress’s policy choices by making it more difficult for Congress to establish uniform national regulatory standards.

Express Preemption Cases Are Different

Even accepting the continued existence of the presumption, the Chamber argues that it has no role in this case because Section 521 of DIDMCA contains an express preemption clause.

The brief emphasizes Supreme Court precedent stating that where Congress has expressly defined the scope of preemption, courts should focus on the statutory text rather than invoke presumptions favoring state authority.

According to the Chamber, the district court correctly followed this approach when it concluded that the “inquiry begins and ends with statutory language when its meaning is plain.”

The Chamber also notes that the Tenth Circuit itself has repeatedly recognized that the presumption against preemption does not apply in express-preemption cases.

Federal Interests in Banking Override Any Presumption

The Chamber additionally argues that even if some version of the presumption survives in express-preemption cases, it should not apply here because banking is an area characterized by a longstanding and substantial federal presence.

The brief reviews the extensive federal regulation of both state and national banks, including:

• FDIC supervision and deposit insurance requirements;
• Federal safety-and-soundness standards;
• Federal consumer financial protection statutes;
• Congress’s longstanding efforts to ensure competitive equality between state and national banks.

The Chamber contends that DIDMCA was enacted precisely to create a uniform national framework for interest-rate exportation and to prevent states from undermining interstate banking through conflicting interest-rate restrictions.

In the Chamber’s view, the panel majority overstated Colorado’s historical authority in this area because the specific issue presented—whether Colorado may regulate interest rates charged by out-of-state state-chartered banks engaged in interstate lending—is not a traditional field of exclusive state regulation.

Support for Judge Rossman’s Interpretation

Like several other amici supporting the plaintiffs, the Chamber endorses Judge Rossman’s dissenting opinion asserting that the Colorado effort to regulate interest rates of out-of-state state banks is preempted by Section 521 of DIDMCA.

The brief argues that the proper reading of Section 525’s opt-out provision is that a loan is “made” where the lending bank performs its non-ministerial lending functions and is located, rather than where the borrower resides.

According to the Chamber, that interpretation best fits:

• The statutory text;
• DIDMCA’s overall structure;
• The statute’s legislative purpose of creating competitive parity between state and national banks;
• The realities of modern interstate and online banking.

The Chamber warns that the panel majority’s contrary interpretation would create precisely the kind of state-by-state patchwork that Congress sought to eliminate through DIDMCA.