With one notable exception, Nebraska, both the federal and the state legislative bodies are bi-cameral. For example, the New York legislative body is composed of the State Senate and Assembly.

At the federal level, the two congressional chambers are called the Senate and the House of Representatives. Originally, the two chambers had different constituencies and bi-cameralism was supposed to diffuse the eventual tyranny of the majority (mob) and prevent it from legislating against the minority interests. The majority was supposed to speak through representatives, and the minority through senators. Unless the two chambers agree on its content, as shown below, no statute can be enacted. Today, there are no institutional concerns regarding the original role of bi-cameralism-that of removing the legislative power from the mob.

From a structural point of view, the composition of the two chambers is different. First, the number of state representatives in the lower chamber changes after each census, and states with growing populations gain representation. However, each state has only two senators to represent its interests in the Senate. Thus, unlike representatives who represent a specific part of the state’s constituency, each Senator represents the whole state. Second, while all the representatives are elected at the same time, only one third of the senators are elected at any given time.

From a lawmaking point of view, there are few differences between the two chambers. Members of each one can introduce a bill that they want to become a law. A committee of that chamber will study the bill and recommend passage with or without changes. If it reports back to its chamber with recommendations, further action is taken, and the bill goes to the floor for debate. If the bill passes the debate, it is sent to the other chamber where similar debates are expected. When there are proposed amendments, both chambers of Congress must agree on them. When the houses cannot agree on the content of a bill, the bill is referred to a special committee whose role is to resolve differences between the two legislative houses on the wording of a bill. Unless a bill passes both houses in the same form, it cannot be sent to the President for further legislative action. At this point in the lawmaking process, the President has a few options. The President can sign the bill into law. The President can do nothing. Then, if Congress is in session, the bill becomes law automatically after ten days. If Congress is not in session when the ten-day period expires, the bill does not become law. The President can also veto the bill. Then, unless Congress overrides the veto by a two-thirds vote of both houses, the bill does not become law either. Once the bill is signed into law, it becomes binding federal statutory law.
Legislative History - Federal Page
Legislative History - Federal Page


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At the state level, the process is almost identical. A legislator introduces a bill, and then the bill is referred to the appropriate standing committee of the house where it was introduced.

When the bill passes both houses, it is sent to the governor’s office. Like the President, a governor can sign bills into law, veto them, or take no action on them. Once the bill is signed into law, it becomes binding state statutory law.