Final answer:
A veto is the power to formally reject legislation by the executive branch or Governor, while the Supreme Court can strike down laws and actions as unconstitutional through judicial review.
Step-by-step explanation:
The formal, constitutional decision to reject a resolution or bill made by the legislature is known as a veto. The use of the veto is a powerful executive check within the United States governmental system. For example, in 2007, when Governor Doyle used his veto power to alter the budget, it led to significant controversy and the eventual passing of a referendum limiting this aspect of the veto power. The veto enables the governor to either totally reject a bill or, in the case of a line-item veto, reject specific parts of a budget bill while signing the rest into law.
In the judiciary, the power is also vested in the Supreme Court and lower courts to strike down laws and governmental actions that are deemed unconstitutional. This judicial review was established by the Supreme Court case Marbury v. Madison, indicating that any act of the legislature conflicting with the Constitution is void. Vetoes and the checks and balances they are part of ensure that different government branches can exercise control over others to maintain the separation of powers.