In a federal system, public policy is created at multiple levels, allowing for state or regional autonomy, leading to diverse policies tailored to local needs. In contrast, a unitary system centralizes authority, with a primary national government controlling policy formation. This often results in uniform policies but may neglect regional interests. The key difference lies in the distribution of political power: federal systems promote local governance while unitary systems emphasize centralized authority. The effectiveness of public policy may vary significantly based on governance structure, influencing how effectively local concerns are addressed.