Bicameral Legislature
A legislative body divided into two separate assemblies, chambers, or houses. In the U.S., this is the House of Representatives and the Senate, a structure designed to balance the interests of large and small states.
The Constitutional Convention’s Great Compromise of 1787 created Congress’s bicameral structure specifically to balance two competing visions: the Virginia Plan’s call for representation based on population (favoring larger states) and the New Jersey Plan’s call for equal representation per state (favoring smaller states). The compromise gave the House population-based representation and the Senate equal representation — two senators per state — meaning any bill must pass both chambers in identical form before going to the President.
That dual-passage requirement makes bicameralism a genuine structural check, not just an organizational quirk: a bill can pass the House by a wide margin and still die in the Senate, or vice versa, and even minor differences between House and Senate versions of the same bill must be reconciled — often through a conference committee — before either chamber has actually “passed” the same law the other one did.
Common misconception: people often assume the House and Senate are simply two versions of the same kind of body, with the Senate functioning like a slightly smaller, more senior House. Structurally they’re quite different: the Senate’s equal-representation design means California’s roughly 39 million residents and Wyoming’s roughly 580,000 get the same two senators each, a deliberate departure from the population-proportional representation used in the House.