authority

noun:the power or right to give orders, make decisions, and enforce obedience
- The principal has the authority to enforce the school's rules.
noun:a person or organization having control or jurisdiction in a specific area
- The health department is the authority responsible for issuing food safety certifications.
noun:expertise or recognized knowledge in a particular field, making one's statements reliable
- Dr. Smith is an authority on medieval history and has published numerous books on the subject.
noun:confidence resulting from expertise or knowledge
- She spoke with great authority on the subject of ancient history.