Martial Law: Can A President Invoke It?

The question of whether a US president can invoke martial law is a complex one, and the answer is not entirely clear-cut. While the US Constitution does not explicitly grant the president the power to declare martial law, there have been instances in US history where presidents have done so. Martial law refers to when a nation's armed forces assume the governance of an area, typically in times of crisis, war, natural disaster, or civic dispute. While the president is the Commander-in-Chief of the US armed forces, the power to declare martial law may lie with Congress, which has the authority to declare war and provide for its prosecution. The Supreme Court has also never specifically ruled that the president can declare martial law, adding to the ambiguity surrounding this issue.

The US President's power to invoke martial law

The US Constitution does not define martial law and does not specify who can declare it. However, several presidents and many state governors have imposed or approved declarations of martial law throughout American history.

Although the Supreme Court has held that states can declare martial law, it has never explicitly held that the president can. Therefore, it is unclear whether the president can legally declare martial law. However, some scholars believe that the president has the executive power to declare martial law. Others argue that the president requires congressional authorization to impose martial law in a civilian area.

Congress has the power to declare war and provide for carrying on war. This power and duty belong to the president as Commander-in-Chief. Both these powers are derived from the Constitution, but neither is defined by that instrument. Their extent must be determined by their nature and the principles of US institutions.

In 2006, amendments to the Insurrection Act gave the US President new powers to use the military for domestic disturbance, terrorism, insurrection, etc. However, this has been a source of concern for some, who worry about the potential for abuse of power.

Congress's role in authorising martial law

The concept of martial law in the United States and the authority to declare it is not well understood. While the US President does not have the authority to declare martial law, the US Congress has the power to impose it within certain constraints. Congress can authorise a presidential declaration of martial law, but this has not been conclusively decided.

Congress has placed clear and wide-ranging restrictions on the president's ability to use the military domestically. A presidential declaration of martial law would violate these rules. The Constitution does not grant the president "conclusive and preclusive" power over the issue of domestic military deployment. Instead, it gives most of the relevant authority to Congress.

The Insurrection Act and potentially Title 32 allow the president to deploy the military to assist civilian authorities with law enforcement activities. However, this does not imply that the military may push aside civilian authorities. The Posse Comitatus Act also makes it illegal for federal military forces to participate in civilian law enforcement activities unless authorised by Congress.

Congress has enacted a wide variety of laws that regulate when and where the military may be used domestically. These laws are so comprehensive that Congress has "occupied the field", meaning that if the president were to use the military domestically without authorisation, it would be against Congress's will.

In short, Congress has the power to authorise a presidential declaration of martial law, but the president cannot act against Congress's will unless the Constitution grants the president "conclusive and preclusive" power over that issue.

Martial law and the Insurrection Act

The concept of martial law in the United States refers to instances in history when a region, state, city, or the entire nation was placed under the control of a military body. Martial law is generally understood as a power that allows the military to assume the role of civilian government in an emergency. The US Constitution does not expressly provide for the exercise of extraordinary authority in times of crisis. While the president has the authority to deploy troops to assist civilian law enforcement, the president lacks the power to declare martial law. This authority rests with Congress, which can authorize a presidential declaration of martial law. State officials also have the power to declare martial law within their respective states, but their actions must comply with the US Constitution and are subject to federal court review.

The Insurrection Act, originally enacted in 1792, grants the president the authority to deploy the US military and federalized National Guard troops domestically in certain situations, such as to suppress civil disorder, insurrection, rebellion, or domestic violence. The Act has been invoked numerous times throughout US history, including by George Washington and John Adams in response to early rebellions, by Abraham Lincoln at the start of the Civil War, and by Ulysses Grant to crush the Ku Klux Klan. The Insurrection Act does not, however, authorize martial law. Instead, it permits the military to assist civilian authorities, not replace them.

The Insurrection Act has been criticized as dangerously vague and in urgent need of reform to prevent abuses of power. The law does not specify what actions are authorized when it is invoked, and there are few constraints on presidential power. While the Supreme Court has ruled that courts may review the lawfulness of the military's actions, the lack of clear guidelines and the potential for abuse underscore the need for comprehensive reforms to narrow the criteria for deployment and establish checks and balances.

In recent years, there have been calls for presidents to invoke the Insurrection Act, such as during the 2020 George Floyd protests and in response to the Texas National Guard's presence along the southern border. In 2006, the Insurrection Act was amended to permit military intervention without state consent in emergencies hindering law enforcement, but this amendment was repealed in 2008 after facing opposition from all fifty state governors.

Supreme Court rulings on martial law

The Supreme Court has never explicitly stated whether the federal government or the president has the power to declare martial law. However, the Court's 1952 ruling in Youngstown Sheet & Tube Company v. Sawyer provides a framework for evaluating executive power, which could be used to determine whether a president's declaration of martial law exceeds their authority. According to the Youngstown ruling, when Congress has passed a statute on an issue, the president cannot act against Congress's will unless the Constitution grants the president "conclusive and preclusive" power in that area.

The Supreme Court's precedent on martial law is limited, inconsistent, and outdated. The Court has only addressed the issue a handful of times, and the most recent precedent was set almost 75 years ago. The Constitution does not mention martial law, and no federal statute defines it, which makes the scope and limits of martial law unclear.

In 1878, Congress passed the Posse Comitatus Act, prohibiting the US military from engaging in domestic law enforcement without congressional approval. This act places clear restrictions on the president's ability to use the military domestically, which a unilateral declaration of martial law would violate.

The Supreme Court has held that individual states have the power to declare martial law, as long as it is authorised by the state's constitution or laws. For example, in 1942, the Court found that the Constitution applied to Hawaii, an incorporated territory, and that the legality of martial law there should be analysed as if it were a state. In another case, Moyer v. Peabody (1909), the Supreme Court ruled that the state of Colorado did not violate Moyer's right to due process when he was arrested during a labour dispute and martial law.

In Ex parte Milligan (1866), the Supreme Court ruled that President Lincoln's imposition of martial law by suspending habeas corpus was unconstitutional in areas where local courts were still operational. This case involved Lincoln's Congressionally authorised declaration of martial law in Kentucky, Maryland, and Missouri during the Civil War.

State officials' power to declare martial law

The US Constitution does not define martial law and is silent on who can impose it. However, the modern interpretation allows the president and state officials to declare "degrees of martial law in specific circumstances". State officials have the power to declare martial law, but their actions must abide by the US Constitution and are subject to review in federal court.

State martial law power is more clearly established, but there are significant limits. States may declare martial law when authorized by state law, and federal courts will likely defer to a state governor's decision to do so. The US Constitution and valid federal laws will still constrain states' conduct under the declaration, and judicial review will be available in federal court.

State officials have declared martial law in response to violent civil unrest or natural disasters. For example, in the aftermath of the 1900 Galveston hurricane, state officials declared martial law. Far more often, however, they have used martial law to break labor strikes on behalf of business interests. For example, in September 1903, at the request of mine owners, Colorado Governor James Peabody declared martial law in Cripple Creek and Telluride to break a peaceful strike by the Western Federation of Miners.

In nearly every state, the governor has the power to impose martial law within the borders of the state. During the events of the West Virginia Coal Wars (1920–1921), martial law was declared in the state of West Virginia. At the behest of Governor Cornwell, federal troops were dispatched to Mingo County to deal with the striking miners.

Congress might be able to authorize a presidential declaration of martial law, but this has not been conclusively decided.

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