The system of checks and balances in government was developed to ensure that no one branch of government would become too powerful. The framers of the U.S. Constitution built a system that divides power between the three branches of the U.S. government—legislative, executive and judicial—and includes various limits and controls on the powers of each branch.
Separation of Powers
The idea that a just and fair government must divide power between various branches did not originate at the, but has deep philosophical and historical roots.
In his analysis of the government of Ancient Rome, the Greek statesman and historian Polybius identified it as a “mixed” regime with three branches: monarchy (the consul, or chief magistrate), aristocracy (the Senate) and democracy (the people). These concepts greatly influenced later ideas about separation of powers being crucial to a well-functioning government.
Centuries later, the Enlightenment philosopher Baron de Montesquieu wrote of despotism as the primary threat in any government. In his famous work “The Spirit of the Laws,” Montesquieu argued that the best way to prevent this was through a separation of powers, in which different bodies of government exercised legislative, executive and judicial power, with all these bodies subject to the rule of law.
The U.S. System of Checks and Balances
Building on the ideas of Polybius, Montesquieu, William Blackstone, John Locke and other philosophers and political scientists over the centuries, the framers of the U.S. Constitution divided the powers and responsibilities of the new federal government among three branches: the legislative branch, the executive branch and the judicial branch.
In addition to this separation of powers, the framers built a system of checks and balances designed to guard against tyranny by ensuring that no branch would grab too much power.
“If men were angels, no government would be necessary,” James Madison wrote in the Federalist Papers, of the necessity for checks and balances. “In framing a government which is to be administered by men over men, the great difficulty is this: You must first enable the government to control the governed; and in the next place, oblige it to control itself.”
Checks and Balances Examples
Checks and balances operate throughout the U.S. government, as each branch exercises certain powers that can be checked by the powers given to the other two branches.
• The president (head of the executive branch) serves as commander in chief of the military forces, but Congress (legislative branch) appropriates funds for the military and votes to declare war. In addition, the Senate must ratify any peace treaties.
• Congress has the power of the purse, as it controls the money used to fund any executive actions.
• The president nominates federal officials, but the Senate confirms those nominations.
• Within the legislative branch, each house of Congress serves as a check on possible abuses of power by the other. Both the House of Representatives and the Senate have to pass a bill in the same form for it to become law.
• Veto power. Once Congress has passed a bill, the president has the power to veto that bill. In turn, Congress can override a regular presidential veto by a two-thirds vote of both houses.
• The Supreme Court and other federal courts (judicial branch) can declare laws or presidential actions unconstitutional, in a process known as judicial review.
• In turn, the president checks the judiciary through the power of appointment, which can be used to change the direction of the federal courts
• By passing amendments to the Constitution, Congress can effectively check the decisions of the Supreme Court.
• Congress (considered the branch of government closest to the people) can impeach both members of the executive and judicial branches.
Checks and Balances in Action
The system of checks and balances has been tested numerous times throughout the centuries since the Constitution was ratified.
In particular, the power of the executive branch has expanded greatly since the 19th century, disrupting the initial balance intended by the framers. Presidential vetoes—and congressional overrides of those vetoes—tend to fuel controversy, as do congressional rejections of presidential appointments and judicial rulings against legislative or executive actions. The increasing use of executive orders (official directives issued by the president to federal agencies without going through Congress) are another examples of the increasing power of the executive branch. Executive orders are not directly provided for in the U.S. Constitution, but rather implied by Article II, which states that the president “shall take Care that the Laws be faithfully executed.” Executive orders can only push through policy changes; they cannot create new laws or appropriate funds from the United States treasury.
Overall, the system of checks and balances has functioned as it was intended, ensuring that the three branches operate in balance with one another.

Roosevelt and the Supreme Court

A political cartoon that was captioned 'Do We Want A Ventriloquist Act In The Supreme Court?' The cartoon, a criticism of FDR's New Deal, depicts President Franklin D. Roosevelt with six new judges likely to be FDR puppets, circa 1937.

The checks and balances system withstood one of its greatest challenges in 1937, thanks to an audacious attempt by Franklin D. Roosevelt to pack the Supreme Court with liberal justices. After winning reelection to his second term in office by a huge margin in 1936, FDR nonetheless faced the possibility that judicial review would undo many of his major policy achievements.
From 1935-36, a conservative majority on the Court struck down more significant acts of Congress than any other time in U.S. history, including a key piece of the National Recovery Administration, the centerpiece of FDR’s New Deal.
In February 1937, Roosevelt asked Congress to empower him to appoint an additional justice for any member of the Court over 70 years of age who did not retire, a move that could expand the Court to as many as 15 justices.
Roosevelt’s proposal provoked the greatest battle to date among the three branches of government, and a number of Supreme Court justices considered resigning en masse in protest if the plan went through.
In the end, Chief Justice Charles Evans Hughes wrote an influential open letter to the Senate against the proposal; in addition, one older justice resigned, allowing FDR to replace him and shift the balance on the Court. The nation had narrowly averted a constitutional crisis, with the system of checks and balances left shaken but intact.

The War Powers Act and Presidential Veto
The United States Congress passed the War Powers Act on November 7, 1973, overriding an earlier veto by President Richard M. Nixon, who called it an “unconstitutional and dangerous” check on his duties as commander-in-chief of the military. The War Powers Act, created in the wake of the Korean War and during the controversial Vietnam War, stipulates that the president has to consult with Congress when deploying American troops. If, after 60 days, the legislature does not authorize the use of U.S. forces or provide a declaration of war, the soldiers must be sent home.
The War Powers Act was put forth by the legislature to check the mounting war powers exercised by the White House. After all, President Harry S. Truman had committed U.S. troops to the Korean War as part of a United Nations “police action.” Presidents Kennedy, Johnson and Nixon each escalated the undeclared conflict during the Vietnam War.
Controversy over the War Powers Act continued after its passage. President Ronald Reagan deployed military personnel to El Salvador in 1981 without consulting or submitting a report to Congress. President Bill Clinton continued a bombing campaign in Kosovo beyond the 60-day time in 1999. And in 2011, President Barack Obama initiated a military action in Libya without congressional authorization. In 1995, the U.S. House of Representatives voted on an amendment that would have repealed many of the Act’s components. It was narrowly defeated.

State of Emergency
The first state of emergency was declared by President Harry Truman on December 16, 1950 during the Korean War. Congress did not pass The National Emergencies Act until 1976, formally granting congress checks on the power of the president to declare National Emergencies. Created in the wake of the Watergate scandal, the National Emergencies Act included several limits on presidential power, including having states of emergency lapse after a year unless they are renewed.
Presidents have declared almost 60 national emergencies since 1976, and can claim emergency powers over everything from land use and the military to public health. They can only be stopped if both houses of the U.S. government vote to veto it or if the matter is brought to the courts.
Recent declarations include President Donald Trump’s February 15, 2019 State of Emergency to obtain funding for a border wall with Mexico, in which he wrote: “The current situation at the southern border presents a border security and humanitarian crisis that threatens core national security interests and constitutes a national emergency.”