Certain powers in a federal system are possessed by both the national and state governments. These authorities, existing simultaneously at both levels, allow for a degree of shared governance. Examples of these shared authorities include the power to tax, build roads, and establish lower courts. Such arrangements reflect a design intended to distribute governmental functions between the different levels within the system.
The existence of these shared authorities is crucial for flexibility within the federal structure. It allows both levels of government to address issues and needs that may overlap or require a coordinated response. Historically, disputes over the precise boundaries of these shared authorities have been a recurring theme in constitutional interpretation, shaping the evolving relationship between the national and state governments. This dynamic interplay fosters a system of checks and balances, preventing either level of government from becoming overly dominant.