Montesquieu's concept of separation of powers has profoundly shaped modern constitutional systems. By dividing government authority into distinct branches, this principle aims to prevent the concentration of power and safeguard against tyranny.

Modern democracies implement checks and balances to ensure each branch can limit the others' actions. These include the executive's veto power, the legislature's impeachment authority, and the judiciary's power of constitutional review. This system promotes accountability and protects individual liberties.

Separation of Powers

Division of Government Powers

• Separation of powers divides government authority into distinct branches (executive, legislative, judicial) to prevent concentration of power and provide checks and balances
• Each branch has specific roles and responsibilities outlined in the constitution
• Branches have some overlapping powers and ability to limit other branches' actions
• Goal is to prevent tyranny and abuse of power by any single branch

Executive Checks on Legislative Branch

• Veto power allows the executive (president) to reject legislation passed by the legislature
  • Veto can typically be overridden by a supermajority vote in the legislature
  • Pocket veto occurs when president takes no action and Congress adjourns within 10 days
• Executive nominates judges, cabinet members, and other key officials, but legislature must confirm appointments
• In parliamentary systems, executive is chosen by the legislature and can be removed via no confidence vote

Legislative Checks on Executive and Judicial Branches

• Legislature can override executive veto with a supermajority vote (usually 2/3)
• Impeachment power allows legislature to remove executive or judges from office for serious misconduct
  • Impeachment process begins in lower house of legislature, trial occurs in upper house
  • Conviction and removal requires supermajority vote in upper house
• Legislature controls government budget and funding for executive agencies
• Senate has power to ratify treaties and confirm presidential appointments

Judicial and Legislative Oversight

• Courts can rule executive actions and laws unconstitutional via judicial review
• Legislative committees conduct investigations and oversight hearings of executive branch actions
• Legislature can compel testimony and subpoena documents from executive branch officials
• Independent counsels and special prosecutors can be appointed to investigate executive misconduct

Federalism and Bicameralism

Federalism: Vertical Division of Power

• Federalism divides power vertically between central government and regional governments (states, provinces)
• Federal government has authority over national issues (defense, foreign policy, currency)
• Regional governments have power over local issues (education, law enforcement, infrastructure)
• Some policy areas involve overlapping or shared jurisdiction (taxation, transportation, healthcare)
• Federalism allows for regional variation in laws and policies to suit local preferences

Bicameralism: Two Legislative Houses

• Bicameral legislature consists of two separate legislative chambers or houses
• Upper house (Senate) represents states/regions equally, lower house (House of Representatives) representation based on population
• Having two houses limits ability of one faction to control legislative process
• Legislation must pass both houses, allowing for longer deliberation and compromise
• Bicameralism is common in federal systems, with upper house giving equal voice to states/provinces

Judicial Review and Constitutional Amendments

Constitutional Democracy and Judicial Review

• Constitutional democracy limits government power through a written constitution outlining rights and responsibilities
• Constitution is the supreme law of the land and all other laws/government actions must comply with it
• Judicial review gives courts power to invalidate laws and executive actions that violate the constitution
  • Marbury v. Madison (1803) established judicial review in the United States
  • Many other democracies have adopted judicial review, but some limit it to a specialized constitutional court
• Judicial review seen as a key check against "tyranny of the majority" and government overreach

Constitutional Amendment Process

• Constitutions include an amendment process for making changes or additions to the constitution
• Amendment process typically requires a supermajority vote in the legislature and/or public ratification
  • U.S. Constitution can be amended with 2/3 vote in both houses of Congress plus ratification by 3/4 of states
  • Some countries also allow public initiatives to amend constitution (Switzerland, California)
• Amendments used to respond to changing societal needs and values (voting rights, prohibition)
• More difficult amendment process creates stability, but also inflexibility to change
• Judicial interpretation of constitution can change over time even without formal amendments