The US Supreme Court's ability to declare an Act of Congress unconstitutional arises from the implied power of judicial review.
If the US Supreme Court declares an Executive Order (Presidential action) unconstitutional, it is checking the Executive Branch.
No, an Appeals Court cannot 'find' a law unconstitutional. They might declare a law to be unconstitutional IN THEIR BELIEF, but they can only overturn the decision of the lower court and/or return it to them for further action or consideration. Only the U.S. Supreme Court can find a law unconstitutional.
The executive branch is responsible for implementing and enforcing laws. However, the supreme court has the power to deem any action unconstitutional or unlawful, and prevent or undo those actions.
Judicial review is the power to declare a government action that violates some provisions of the constitution to be null and void. This is as a result of the action being in contravention with the provisions of the constitution.
A governmental action that denies someone fair and equal treatment under the law may be declared unconstitutional. A judge can evaluate a law and declare that it is unconstitutional.
Determine whether a president's actions violate the constitution.
Unconstitutional
The Supreme Court can declare a number of things unconstitutional, as long as the it involves an issue relevant to a case before the Court:Federal lawState or municipal lawState constitutional provisionsA particular application of an otherwise constitutional federal lawA particular application of an otherwise constitutional state lawGovernment policies (includes schools, etc).US TreatiesExecutive OrdersCorporate policies or acts of corporate entities or people acting as agents of those entities.Certain military actions or policiesAny action or policy of any entity, if it is repugnant to the Constitution.
A governmental action that denies someone fair and equal treatment under the law may be declared unconstitutional. A judge can evaluate a law and declare that it is unconstitutional.
Judicial ReviewArticle III (constitutional) federal courts in the Judicial Branch of government may declare a law unconstitutional under the doctrine of judicial review, but only if the law is relevant to a case or controversy before the court. The US Supreme Court is the final arbiter of constitutionality, however, and may overturn the lower courts' decision on appeal.The only federal courts that have this power are:US District CourtsUS Court of International TradeUS Court of Appeals Circuit CourtsSupreme Court of the United States
The Marbury v. Madison case established the principle of judicial review, which gives the Supreme Court the power to declare laws and executive actions unconstitutional. This landmark decision, issued in 1803, affirmed the Court's role as a check on the legislative and executive branches, ensuring that no law or action could supersede the Constitution. As a result, the Supreme Court gained significant authority in interpreting the law and maintaining the balance of power within the federal government.
If it is only CLAIMED that the act was unconstitutional, it will take action, initiated in Federal Court, to decide the issue.