What Are the Three Branches of U.S. Government and How Do They Work Together?

The idea of the three branches of the U.S. government isn't a totally American one. "The idea of separate branches and mixed government went all the way back to antiquity and Aristotle's "Politics," something the framers were well aware of," Nicholas Mosvick explains via email. He's a senior fellow at the National Constitution Center, a museum and civil education organization in Philadelphia.

James Madison, the future president who was lead author of the U.S. Constitution, and the other founders also were influenced by John Locke, the late 17th-century British philosopher.

But the most prominent influence may have been French philosopher Baron de Montesquieu, author of the 1748 treatise "The Spirit of the Laws," who described what should distinguish Republican self-government from monarchies and despotic countries. The republican government, he believed, needed to have separate and independent executive, legislative and judicial branches, in order to prevent one another from abusing their various powers.

The system devised by the founders, which is described in Articles I, II, and III of the U.S. Constitution, wasn't quite as cut-and-dried as Montesquieu's, Mosvick says. Instead, they allowed some overlap.

"The easiest examples are in the Senate and Article II," says Mosvick. "The Senate clearly holds executive functions, as they perform a role in advice and consent for treaties, the appointment of judges and executive officers. The president holds a veto power, which gives him a role in legislation, and he has the power to give advice to Congress, typically in the form of a State of the Union and recommendations on legislation."

To make things more complicated, some of the president's powers aren't precisely spelled out in the Constitution, Mosvick explains. "Neither executive orders nor signing statements come from the Constitution's text. Executive orders were a power derived from the implied 'executive power,' 'commander in chief,' and 'faithfully execute' language of Article II, along with the power to command the opinions of executive officers, which led Washington to create the cabinet."

"Signing statements are of significant constitutional debate," Mosvick continues. "Many scholars do not believe that they are constitutional precisely because they violate the separation of powers in that they take on the legislative power by determining the letter of the law when 'faithful execution' merely means to follow the law according to Congress."

The concept of how the three branches work together — or against each other — also has evolved over the centuries.

"The most significant change to separation of powers is likely the rise of the administrative state since the New Deal and the 1930s," Mosvick says. "The Supreme Court was heavily involved in the 1930s in determining the boundaries of what we call delegation — the granting of one branch's powers to an independent body or as part of the executive branch. Some delegations were initially struck down under the non-delegation doctrine. Scholars debate whether or not the non-delegation doctrine flows from the understanding of the founders, but the idea is simply that Congress cannot delegate its core power from the vesting clause — to make all laws — to another body, any more than it can grant non-Article III courts Article III powers or jurisdiction."

"This too is where recent questions about removal of directors of administrative agencies by the president comes from — it too is a separation of powers question, but one that flows from modern innovations that the founders could not entirely envision."

Bruce Peabody is professor of government and politics at Fairleigh Dickinson University and author of "Where Have All the Heroes Gone? The Changing Nature of American Valor," as well as a 2019 article in The Conversation on the separation-of-powers concept. He explains in an email that the checks and balances baked into the three-branch system have prevented abuses of power in the past.

"One of the classic examples is the push and pull associated with the congressional investigation into the Nixon campaign's trespass and bugging of the Watergate building and the Democratic National Committee's headquarters," he says.

"Congress rightfully investigated, the president pushed back, claiming that the White House recordings which implicated the president were covered under the legal protection of 'executive privilege,' and the Supreme Court helped navigate the dispute, ultimately ruling that the president did have the unwritten constitutional power of the executive privilege, but noting that it was not an unlimited power – and setting out some of the rules for its use.

"In the process of this dramatic example of checks and balances, each branch arguably served its own political and institutional interests as well as the nation's," he says.

But the three-branch system isn't some sort of government machine that can run on autopilot. In order for the democracy to work, the people in the three branches need to have personal qualities that go beyond the architecture of the system, Peabody and other scholars say. In recent years, we've seen the system become less effective in working out conflicts and taking effective action. The increasingly acrimonious stalemate over the nation's immigration policy is a prime example.

"I would probably attribute our logjam and chronic inaction most directly to hyperactive partisanship. But, yes, this development is tied up with a decline in our belief in republican virtue, a somewhat old-fashioned idea that our leaders should be expected to act for the public good, not just personal interest, and that they should achieve honor while serving in government," Peabody says. He cites the example of George Washington, who agreed to serve as president of both the constitutional convention and as the first U.S. president out of a sense of duty, even though he was eager to return to his slave-supported estate in Mount Vernon.

Peabody cites the work of scholars Steven Levitsky and Daniel Ziblatt, whom he says have identified basic norms that are necessary for enabling our government to function. One of their key principles, Peabody explains is "mutual toleration" — the idea of accepting your political opponents as legitimate, even if you vehemently disagree with them. Another important ingredient is "forbearance," which basically means that you self-impose limits on how far you'll go in using your powers of government to advance your interests and those of the political party to which you belong.

Nevertheless, America's three-branch system also is highly susceptible to developing imbalances, in part because the founders chose to create a strong chief executive. That leader has broad authority and can't easily be removed from power before his certain number of years are up. (In the U.K., by contrast, political conflict can lead to Parliament calling an early election that can lead to the prime minister being kicked out of power.)

To exacerbate the problem, over the years we've seen a gradual expansion of presidential power. Peabody says that the U.S. government has become increasingly president-centric for a variety of reasons, from changes in our media environment and political campaigns that focus on candidates rather than ideas, to the growth of what's sometimes called the administrative state — the vast, permanent bureaucracy of executive branch agencies.

"This, combined with both parties' post-FDR success in placing their candidates in the White House (and the close competitiveness of many presidential races) have made both Democrats and Republicans complicit in increasing executive power," Peabody says. Both the Trump and Obama administrations, he says, "illustrate that we look to our chief executive to solve problems and wield authority when Congress isn't able to cooperate, lead or assert itself."

After years of infighting in Congress over immigration, for example, President Obama in 2014 decided to issue an executive order deferring the deportation of "dreamers," the children who entered the U.S. illegally with their parents and grew up here, as this National Public Radio story details. The constitutionality of that action was upheld in a narrow 5-4 decision by the U.S. Supreme Court in June 2020. (That ruling is compelling the Trump administration, which had wanted the courts to overturn Obama's Deferred Action for Childhood [DACA] program, to decide whether or not to take the politically unpopular step of dismantling it through a similar executive order.)

But even so, the three-branch system has an amazing amount of resilience. As Peabody notes, the Constitution still enables Congress and the courts to push back against presidential power.

"Despite having a majority of Republican appointees, the justices of the Supreme Court and lower federal courts have provided some checks to presidential overreach," Peabody says. Additionally, "Congress retains the so-called power of the purse, which it can exercise to re-direct national priorities."

Current Speaker of the House Nancy Pelosi has fought to protect Congress's power in the system, by arguing that the Constitution is focused on the procedures and authority of the legislative branch.

"While extremely difficult in our hyper-partisan era, one could at least imagine a nimble Speaker asserting him or herself against an overstepping president and consistently making the case for what political value an engaged Congress provides," Peabody says.

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