Step 1: Understanding the Question:
The question asks about the specific source of law that consists of the declaration of legal rules by a competent authority.
This requires identifying the distinct characteristics of different sources of law.
Step 2: Key Concepts and Approach:
We must distinguish between the main sources of law: legislation, precedent, and custom.
We need to identify which of these is defined by the formal declaration of rules by a designated sovereign or competent authority.
Step 3: Detailed Explanation:
• Definition of Legislation: Legislation is the formal declaration of legal rules by a competent authority, typically the legislature.
• Precedents vs. Legislation: Precedents are judicial decisions made by courts. While they lay down legal principles, their primary function is to resolve specific disputes, not to declare general rules prospectively.
• Customs vs. Legislation: Customs are long-established practices that gain the force of law over time through continuous usage, rather than formal declaration.
• Analytical Positivism: Positivist jurists like John Austin emphasized that legislation is a direct command of the sovereign, reflecting a conscious law-making process.
• Salmond's Classification: Salmond classifies legislation as a legal source of law because it has an authoritative declaration behind it.
Step 4: Final Answer:
Thus, the source of law consisting of the declaration of legal rules by a competent authority is legislation.