This nonpartisan policy brief, written by an ACE fellow, is republished by The Fulcrum as part of our partnership with the Alliance for Civic Engagement and our NextGen initiative — elevating student voices, strengthening civic education, and helping readers better understand democracy and public policy.

Key Takeaways

• Core Constitutional Debate: Expanded ICE enforcement under the Trump Administration raises a core constitutional question: Does Article II executive power override Article I’s congressional power of the purse?
• Executive Justification: The primary constitutional justification for expanded ICE enforcement is The Unitary Executive Theory.
• Separation of Powers: Critics argue that the Unitary Executive Theory undermines Congress’s power of the purse.
• Moral Conflict: Expanded ICE enforcement has sparked a moral debate, as concerns over due process and civil liberties clash with claims of increased public safety and national security.

Where is ICE Funding Coming From?

Since the beginning of the current Trump Administration, immigration enforcement has undergone transformative change and become one of the most contested issues in the federal government. On his first day in office, President Trump issued Executive Order 14159, which directs executive agencies to implement stricter immigration enforcement practices. In order to implement these practices, Congress passed and President Trump signed into law the One Big Beautiful Bill Act (OBBBA), a budget reconciliation package that paired state and local tax cuts with immigration funding. This allocated $170.7 billion in immigration-related funding for the Department of Homeland Security (DHS) to spend by 2029.

Immigration and Customs Enforcement (ICE), a federal law enforcement agency within DHS, received approximately $75 billion of the allocated $170.7 billion. This additional funding from the OBBBA paved the way for increased ICE enforcement and detention in the United States, which has led to controversy.

How Does Congress Allocate Funding for Agencies Like ICE?

When passing the OBBBA, Congress used a special legislative procedure called the budget reconciliation process, which was established through the Congressional Budget Act of 1974 (CBA). The CBA created the House and Senate Budget Committees, which hold responsibility for drafting an annual budget resolution. This resolution is a non-binding agreement that acts as a blueprint for federal spending, but does not become law or require the President’s signature. The CBA also established procedures that govern the congressional budget process.

The budget reconciliation process is an example of one of these procedures. It allows Congress to fast-track legislation that modifies existing law related to spending, taxes, or the debt limit, in order to ensure implementation of priorities laid out in the annual budget resolution. Specifically, the budget reconciliation process expedites legislation by only requiring a majority vote in the Senate, therefore avoiding the threat of a filibuster. This procedural advantage proved critical to the passage of the OBBBA, which cleared the Senate on a tiebreaking vote cast by Vice President J.D. Vance.

The Legal Framework For The ICE Funding Debate

On a legal basis, the controversies surrounding ICE’s actions under the Trump Administration stem from different interpretations of the United States Constitution. In short, Article I of the Constitution gives Congress the power to authorize the spending of public money and raise revenue via taxation, known as the power of the purse, while Article II vests executive power in the President of the United States.

While the Constitution precisely lays out these distinct powers, tensions arise when they overlap. Recently, debate has sparked over how the executive branch allocates congressionally appropriated funds within ICE. In this debate, proponents of expanded executive discretion argue that since ICE is an executive agency under the DHS umbrella, the President has broad discretion to allocate funds within ICE. Comparatively, critics of expanded executive discretion argue that because Congress has the power of the purse, they have the authority to shape spending priorities and constrain how executive agencies spend the money allocated to them.

Unitary Executive Theory

One prominent framework supporting expanded executive discretion is the Unitary Executive Theory, a constitutional law theory holding that the President of the United States possesses broad authority to direct and control the executive branch. Under this view, executive agencies are viewed as extensions of the President’s power rather than as independent actors.

Proponents of this theory argue that once Congress has appropriated funds to an executive agency, the President has the constitutional authority to determine how those funds are allocated. Because the OBBBA appropriated additional funds to the DHS, the Unitary Executive Theory has been used to justify President Trump’s discretion over how those funds are being allocated, a significant portion of which are directed towards expanded ICE enforcement, detention, and removal operations.

Separation of Powers

A contrasting framework of the United States Constitution rejects expanded executive discretion and emphasizes Article I of the United States Constitution, which gives Congress power of the purse, and establishes separation of powers. This viewpoint claims that executive agencies are not merely extensions of presidential power, but rather, institutions that must be constrained by statute.

Simply put, proponents of this framework argue that even though executive agencies operate within the executive branch, they ultimately exist because Congress creates them through law. Accordingly, proponents contend that because Congress creates these agencies and controls their funding, it should retain the authority to set spending priorities and impose constraints on how appropriated funds are used.

Support for Executive Discretion and Expanding ICE’s Power

Supporters of executive discretion in funding agencies like ICE often cite Article II of the United States Constitution and the Unitary Executive Theory, which rose to prominence through Justice Antonin Scalia’s dissent at the conclusion of the Supreme Court case Morrison v. Olson. Scalia’s interpretation of Article II is that all executive power is vested in the President of the United States. Under this interpretation, the President is authorized to control the funding decisions that executive agencies make within statutory limits.

While Congress has the power of the purse, this position argues that an executive agency should not be obligated to balance its spending choices with what Congress desires, as the money has already been congressionally appropriated to it. Supporters of this view justify President Trump’s decision to expand ICE enforcement and detention priorities, interpreting that under Article II, the President has the power to allocate funds in an agency within statutory bounds.

In addition to the Unitary Executive Theory, individuals against limiting executive discretion and ICE’s power argue that the Supremacy Clause, which establishes federal law as the supreme law of the land, is a constitutional justification for the expansion of ICE enforcement and detention. This interpretation of the constitution challenges attempts from local and state governments to remove ICE agents from their jurisdiction. Supporters of ICE saw a legal win on February 2, 2026, when US district judge Katherine Menendez declined to halt Operation Metro Surge over a lawsuit filed by Minnesota and the city of Minneapolis against the DHS. In her ruling, Menendez indicated that Minnesota had not demonstrated a sufficient likelihood of proving a Tenth Amendment violation, and that halting ICE operations would prevent the Federal Government from carrying out constitutionally authorized duties.

On a moral level, individuals in favor of expanded ICE operations argue that increased enforcement directly improves national security and public safety. The DHS released information claiming that over the first six weeks of Operation Metro Surge, federal law enforcement arrested 3,000 criminal illegal aliens. The DHS further claims that this number includes, “vicious murderers, rapists, child pedophiles, and incredibly dangerous individuals,” therefore greatly benefiting public safety.

While opponents of expanded ICE enforcement and detention frequently cite the deaths of Alex Preti and Renee Good as examples of the drawbacks of expanded ICE power, The Heritage Foundation refutes this point. Heritage claims Minnesota Governor Tim Walz and Minneapolis Mayor Jacob Frey are to blame for these deaths due to their encouragement of anti-ICE protests and refusal to cooperate with DHS law enforcement. Heritage recommends that in order to improve public safety and maximize the effectiveness of ICE’s expanded operations, there should be an increase in workplace enforcement and targeted, unpredictable arrests.

Opposition to Executive Discretion and Expanding ICE’s Power

Proponents of limiting executive discretion believe that the Unitary Executive Theory is a misinterpretation of the United States Constitution. One core argument is that while executive agencies serve presidential functions, they also do both quasi-legislative tasks, such as implementing policies and regulations that carry the force of the law, and quasi-judicial functions, including settling disputes within their agency. For these reasons, critics of the Unitary Executive Theory believe that Congress has the authority to protect executive agencies from political control.

The landmark Supreme Court case Humphrey’s Executor v. The United States reinforces this view. This case holds that when an agency performs both quasi-legislative and quasi-judicial functions, Congress may limit the President’s authority to remove its officials, therefore directly preserving an executive agency’s institutional independence from political control.

Furthermore, critics claim that the Unitary Executive Theory reduces checks on the executive branch and weakens institutional independence, ultimately increasing the concentration of executive power. Because ICE performs functions that involve both rule implementation and case adjudication, critics argue that Congress should have imposed clearer statutory constraints on how the additional $75 billion in funding is directed and used. Instead, the OBBBA grants the executive branch broad discretion over resource allocation within the agency, raising constitutional concerns about whether Congress has adequately exercised its power of the purse or has effectively surrendered its spending authority to the President.

Proponents of limiting executive discretion often point to judicial review under the Administrative Procedure Act (APA) as a major check on executive power. Passed in 1946, the APA governs how federal agencies create and enforce regulations, meaning executive actions must comply with its requirements. The 2024 Supreme Court case Loper Bright Enterprises v. Raimondo strengthened these limits by overturning the Chevron Doctrine and requiring courts, rather than agencies, to independently interpret ambiguous laws. This ruling is especially relevant to recent lawsuits challenging expanded ICE enforcement under Operation Metro Surge, as courts are now more likely to independently assess whether ICE’s actions exceed the authority granted by Congress, rather than referring back to the agency itself.

Critics of expanded ICE powers also raise significant due process, civil liberties, and economic concerns about the scale and scope of ICE operations. Of individuals booked into ICE custody in Fiscal Year 2025, only 5 percent had violent convictions, and 73 percent had no criminal convictions at all. With the White House targeting 3,000 arrests per day, opponents argue this enforcement goal will inevitably sweep up non-criminals, raising concerns that detention is being used as a tool of mass enforcement without regard to individual circumstances or public safety risk.

Conclusion and Future Outlook

Under the current Trump administration, expanded ICE enforcement and detention operations have become a central issue, raising both moral and legal concerns. Proponents of executive discretion ground their legal claims in Unitary Executive Theory, stating that the President has broad authority to allocate funds within executive agencies. Supporters of ICE’s expanded operations argue that heightened immigration enforcement and detention significantly improve public safety. Conversely, proponents of limiting executive discretion ground their legal claims in Article I of the United States Constitution and Supreme Court precedents that limit executive power in allocating the specific use of funds within executive agencies like ICE. Critics of ICE’s expanded operations argue that they neglect due process and basic human rights.

Looking forward, these competing constitutional and moral arguments will continue to shape immigration enforcement, the broader landscape of United States governance, and ongoing debates over the correct balance of power between Congress and the executive branch.

FAQ’s

Q: Who has the authority to spend the funding allocated to ICE and other executive agencies, Congress or the President?

A: Different interpretations of the constitution lead to different answers to this question. While some may believe that Article II of the United States constitution vests all executive power in the President of the United States, this view conflicts with the Power of the Purse given to Congress in Article I.

Q: Is the expansion of ICE enforcement legally justified under the Constitution?

A: There is no single agreed upon answer to this question. Arguments in favor of ICE expansion include the Unitary Executive Theory and the Supremacy Clause. In comparison, arguments against expanded ICE operations cite the APA, Impoundment Control Act, Supreme Court Precedents (Humphreys Executor v. The United States) and recent judicial cases, such as Loper Bright v Raimando — all of which look to limit concentrated executive power and place checks on the executive branch.

Q: Why is the expansion of ICE operations controversial on a moral level?

A: Arguments in favor of expanded ICE operations cite an increase in public safety. Arguments against ICE expansion cite the lack of overall immigration reform, as well as the neglecting of due process and civil liberties for individuals targeted by ICE.

Ronan Kiter is an ACE fellow.

The Power of the Purse and Executive Discretion: ICE Expansion Under the Trump Administration was first published by ACE and republished with permission