All legislative power in the government is vested in Congress, meaning that it is the only part of the government that can make new laws or change existing laws. ... The President may veto bills Congress passes, but Congress may also override a veto by a two-thirds vote in both the Senate and the House of Representatives.
The legislative branch is made up of the two houses of Congress—the Senate and the House of Representatives. The most important duty of the legislative branch is to make laws. Laws are written, discussed and voted on in Congress. ... The Senate must ratify all treaties by a two-thirds vote.
