What is checks and balances?

Checks and balances is the constitutional mechanism by which each of the three branches of the federal government can limit the actions of the other two, preventing any single branch from accumulating unchecked power. James Madison defended the design in Federalist No. 51 in 1788 with the famous observation that ambition must be made to counteract ambition, because if men were angels no government would be necessary.

Each branch is given specific tools to check the others. Congress can pass legislation, but the president can veto it; Congress can override a veto with a two-thirds vote of each chamber. The president nominates federal judges, ambassadors, and senior officials, but the Senate must confirm them. The president negotiates treaties, but the Senate must ratify them by two-thirds vote. Congress controls the federal budget, raises armies, declares war, and may regulate the jurisdiction of lower federal courts. The judiciary, since Marbury v. Madison in 1803, exercises judicial review and may strike down laws or executive actions that violate the Constitution. Congress can impeach federal judges and the president, with the House voting articles of impeachment by majority and the Senate trying the case and removing officers by a two-thirds vote. The president can grant pardons but not for impeachment offenses.

Each branch also depends on the others for resources or appointments. The judiciary needs Congress to fund it and the president to appoint its members. The president needs Congress to fund executive agencies. Congress needs the courts to interpret its statutes and the president to enforce them.

History shows the system at work. Andrew Johnson's impeachment in 1868, the Senate's rejection of the Treaty of Versailles in 1919, the Supreme Court's order in United States v. Nixon in 1974 to turn over White House tapes, the rejection of the Bork nomination in 1987, and the bipartisan congressional investigations of the 2000s and 2010s all involved one branch using its checks against another.

The system trades efficiency for stability. Lawmaking is slower than under a parliamentary system, but no faction can dominate every lever of power simultaneously, and major changes require sustained, broad agreement.