Why has executive power grown in many legislatures during the modern era?

In the modern era, the growth of executive power—often referred to as executive aggrandizement—has been driven by several complex factors across various political systems.123

Drivers of Executive Growth

• Crisis Management: Executives have increasingly assumed greater authority to respond to demanding social, economic, and military crises. In many constitutional democracies, this has included the use of emergency powers during periods of domestic or foreign instability.23
• Technological and Bureaucratic Complexity: The requirements of governing in a technological era necessitate complex decision-making, which has bolstered the role of large bureaucratic structures within the executive branch.23
• Legislative Initiation: Executives in most countries now play a primary role in the lawmaking process by initiating the legislation that is subsequently considered by parliaments and congresses.1
• Foreign Affairs: Executives have increasingly dominated the sphere of foreign affairs, often utilizing devices such as executive agreements to bypass traditional legislative requirements for treaty ratification.1
• Fiscal Control: The rise of the executive budget and specialized budgetary agencies has challenged the traditional fiscal oversight powers previously held by legislatures.1

While these trends have led to a decline in legislative power in many nations, it is not a universal phenomenon; some legislatures, such as the United States Congress, have actively developed new techniques for oversight to maintain their influence.1