Major Sources of U.S. Law and Federal-State Conflicts
This paper examines the principal sources of law under the American system of jurisprudence, including the U.S. Constitution, natural law, administrative law, statutory law, and common law. It explains how these sources generally complement one another while also identifying circumstances in which they conflict. Special attention is given to the Supremacy Clause and the legal concept of "characterization" used to resolve jurisdictional disputes. A hypothetical vignette involving a disabled African American Vietnam veteran arrested in Idaho for possessing medical cannabis legally purchased in Montana illustrates the real-world consequences of unresolved federal-state conflicts, particularly in marijuana law. The paper concludes with a call for nationwide legal harmonization.
- Introduction: Purpose and scope of the paper
- Major Sources of U.S. Law: Constitutional, natural, administrative, and common law
- Complement or Conflict: How Laws Interact: Jurisdictional conflicts and the Supremacy Clause
- Client's Legal Issue: Federal-State Cannabis Conflict: Idaho cannabis vignette and racial disparities
- Conclusion: Synthesis and call for legal harmonization
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What makes this paper effective
- The paper moves logically from abstract legal theory (constitutional foundations, natural law) to concrete application (the cannabis vignette), making complex legal concepts accessible without oversimplifying them.
- The use of a specific hypothetical vignette grounded in real Idaho and Montana law gives the argument practical weight and illustrates the human cost of unresolved legal conflicts.
- Direct quotations from authoritative sources—Black's Law Dictionary, the Cornell Law School Legal Information Institute, and the Supremacy Clause itself—lend credibility and demonstrate appropriate engagement with primary and secondary legal materials.
Key academic technique demonstrated
The paper effectively uses the "general-to-specific" organizational technique: it first establishes a broad conceptual framework (the hierarchy and types of U.S. law), then narrows to a precise legal mechanism (conflict of laws and the Supremacy Clause), and finally applies those principles to a concrete, socially relevant scenario. This layered approach is a hallmark of competent undergraduate legal writing.
Structure breakdown
The paper is organized into five sections. The introduction frames the purpose and scope. The second section surveys the major sources of law in hierarchical order. The third section analyzes how laws interact, including the resolution of conflicts through classification and the Supremacy Clause. The fourth section presents a hypothetical client scenario to illustrate federal-state cannabis conflict. The conclusion synthesizes the key findings and advocates for legal harmonization.
Introduction
Today, most Americans are rightfully proud of the fact that the United States is a land of laws, but many may not realize the multiple sources of the laws that routinely affect their daily lives (Lupu, 2013). The purpose of this paper is to provide a description of the major sources of law under the American system of jurisprudence and how these different sources of law either complement or conflict with one another. In addition, a hypothetical vignette describing a potential conflict between federal and state law concerning the possession of medical cannabis products in Idaho is presented, followed by a summary of the research and important findings in the conclusion.
Major Sources of U.S. Law
Far and away, the major source of law in the United States is the Constitution, from which all other laws, policies, and regulations flow. In this regard, the Chicago Council of Lawyers (2022) emphasizes that "the U.S. founders learned from King George and others like him that they wanted and needed a country governed by the rule of laws, not of men. The Rule of Law in the United States does not begin with the President. It does not begin with any political party. It begins with our Constitution" (The United States is a nation ruled by laws, not kings, 2022, para. 4). Likewise, state constitutions are also a primary source of law across the country. Another prime source of laws in the United States is natural law, which is discussed below.
One of the other major sources of law in the United States is natural law. The definition provided by Black's Law Dictionary (1990) notes that the term "natural laws" is used to "denote a system of rules and principles for the guidance of human conduct which [are] independent of an active law or the systems peculiar to any one people" (p. 1026). In other words, natural laws take priority over manmade laws when they conflict. One legal authority points out that Roger Williams, the founder of Providence Plantations (which would later become Rhode Island), maintained that "all political acts, which are not in accord with the natural law are merely acts of violence" (as cited in Higdon, 2021, p. 85). In reality, many natural laws — such as the fundamental right to self-defense and religious liberty — have long been formally codified into American jurisprudence (Higdon, 2021).
Other major sources of American law include administrative laws such as rules, regulations, directives, and orders promulgated by the executive branch of the federal government (Sources of law, 2022). Executive orders and directives are issued by the U.S. president, while rules and regulations are made by federal administrative agencies such as the Environmental Protection Agency (Sources of law, 2022). In addition, various statutes are created by the legislative branch of government, while the judicial branch generates case law and legal opinions that comprise the common law, which is subject to continuous review and change (Sources of law, 2022). One legal authority reports that "in a common law system, the law is expressed in an evolving body of doctrine determined by judges in specific cases, rather than in a group of prescribed abstract principles" (Sources of law, 2022, para. 5). In fact, only Louisiana maintains adherence to the Napoleonic civil law rather than the common law today. Although the common law "evolves" over time in response to changes in prevailing social norms and values, it is still heavily influenced by the doctrine of stare decisis, which generally requires courts to follow the precedent established by previous cases (Sources of law, 2022).
Complement or Conflict: How Laws Interact
A conflict of law occurs when two or more jurisdictions have laws in place with some common element that creates the need to determine which jurisdiction's law will prevail in resolving a legal matter (Conflict of laws, 2022). Such conflicts can arise with respect to federal laws, state laws, or even laws from other nations, and the overarching consideration in resolving them involves determining which jurisdiction's laws should be applied. According to legal authorities at the Cornell Law School Legal Information Institute, this determination of the most appropriate jurisdiction is termed "classification" or "characterization" (Conflict of laws, 2022).
In cases of conflict involving diversity of citizenship, for example, the "law of the forum" (lex fori) can be applied. Conversely, in cases where the conflict involves procedural issues such as a monetary transaction, courts can elect to apply the lex loci approach, which designates the site of the transaction as the appropriate jurisdiction to adjudicate the matter (Conflict of laws, 2022). It is important to note, however, that in cases of conflict, federal laws are generally superior to state laws. The Legal Information Institute reports that "Article VI, Paragraph 2 of the U.S. Constitution is commonly referred to as the Supremacy Clause. It establishes that the federal constitution, and federal law generally, take precedence over state laws, and even state constitutions" (Supremacy clause, 2022, para. 3). This type of conflict can occur when federal and state laws are not harmonized — such as the current situation with cannabis laws in the United States — and a vignette illustrating such differences is presented below.
Conclusion
The major sources of law in the United States include federal and state constitutions, natural and administrative laws, and the common law (except for Louisiana, which subscribes to the civil law). Although state and federal laws are generally aligned, in those cases where they conflict, the Constitution's Supremacy Clause stipulates that federal law will prevail. The research also showed that determining the appropriate venue for adjudicating a case is known as "classification" or "characterization," and this determination is necessary when laws conflict. Finally, the research also showed that justice is not always served when conflicts of law occur, but the common law continues to evolve in ways that help eliminate such injustices from the American system of jurisprudence.
References
Black's law dictionary. (1990). St. Paul, MN: West Publishing Company.
Chicago Council of Lawyers. (2022). The United States is a nation ruled by laws, not kings. Retrieved from https://chicagocouncil.org/072220-nation-ruled-by-laws-not-kings/
Conflict of laws. (2020). Cornell Law School Legal Information Institute. Retrieved from https://www.law.cornell.edu/wex/conflict_of_laws
Higdon, C. D. (2021). Roger Williams, natural law, and religious liberty. Journal of Church & State, 63(1), 85–108.
Idaho State Supreme Court. (2021, August 25). Marijuana Policy Project. Retrieved from https://www.mpp.org/states/idaho/
Lupu, R. (2013). Sources of law — judicial precedent. Contemporary Readings in Law & Social Justice, 5(2), 375–381.
Sources of law. (2022). UC Hastings Law Library. Retrieved from
State marijuana laws. (2022). Marijuana Policy Project. Retrieved from https://www.mpp.org/issues/legalization/state-marijuana-regulation-laws-are-not-preempted-by-federal-law/
Supremacy clause. (2022). Cornell Law School Legal Information Institute. Retrieved from https://www.law.cornell.edu/wex/supremacy_clause
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