The History of Bicameralism
The ideas which underlie bicameralism may be traced back to the theories developed in ancient Greece and Rome, though recognisable bicameral institutions arose first in medieval Europe where they were associated with separate representation of different estates of the realm. The American Founding Fathers eschewed any notion of separate representation for a social aristocracy, but accepted the prevailing disposition towards bicameralism. However, they then invented a new rationale for bicameralism linked with federalism. In subsequent constitution-making, federal states have invariably adopted bicameralism, but the older justification for second chambers as providing opportunities for second thoughts about legislation has survived. A trend towards unicameralism in the twentieth century appears now to have been halted. Growing awareness of the complexity of the notion of representation and the multi-functional nature of modern legislatures may be affording incipient new rationales for second chambers though these do generally remain contested institutions in ways that first chambers are not.