This case examines the constitutionality of a provision in the Immigration and Nationality Act that allowed one House of Congress to veto the Executive Branch's decision to allow a deportable alien to remain in the US. The Supreme Court held that the House lacked constitutional authority to order Chadha's deportation and that the statute violated the separation of powers doctrine. The provision for the one-House veto was found to be severable from the remainder of the Act. The Court of Appeals had jurisdiction to hear Chadha's constitutional challenge, and the Supreme Court has jurisdiction over Chadha's challenge to Congress' authority. This case has implications for the use of congressional veto provisions in statutes delegating authority to executive and independent agencies.

Justice Powell agrees with the Court's decision to invalidate the legislative veto based on the Presentment Clauses, but expresses concern about Congress assuming a judicial function when finding that a person does not meet the criteria for permanent residence. This violates the principle of separation of powers, which the Framers of the Constitution established to prevent tyranny. The Bill of Attainder Clause prohibits legislative punishment without a judicial trial, which is an implementation of the separation of powers. Congress violated the doctrine by assuming a judicial function when vetoing the Immigration and Naturalization Service's decision to suspend Chadha's deportation, who met the criteria for permanent residence in the US.

The legal case discusses the Supreme Court's decision to invalidate the legislative veto mechanism in § 244(c)(2) of the Immigration and Nationality Act. Justice White dissented, arguing that the legislative veto is necessary for Congress to ensure accountability of executive and independent agencies. The Court found that the disapproval of a suspension of deportation by one House of Congress through the legislative veto is an exercise of legislative power that does not comply with the prerequisites for lawmaking set forth in Article I. The Court's decision suggests that Congress may not reserve a veto power over suspensions of deportation for itself, but can delegate it to private hands or independent agencies. The legislative veto serves as a necessary check on the expanding power of agencies delegated authority by Congress. The lower court erred in ruling the legislative veto unconstitutional, as it has been used to balance broad delegations in legislation, limit Executive-Legislative confrontations, and preserve congressional authority.

Justice Rehnquist's dissenting opinion, joined by Justice White, argues that while a severability clause creates a presumption that valid portions of a statute remain in force when one part is found to be invalid, it does not conclusively resolve the issue. The determination ultimately depends on the intent of lawmakers, and the presence or absence of a severability clause is not always decisive. In this case, Justice Rehnquist believes that Congress did not intend the one-House veto provision of § 244(c)(2) to be severable, as it is an exception to the general rule of suspending deportation when statutory criteria are met. Exceptions like this are typically not severable, and therefore, Justice Rehnquist dissents. The dissenting opinion asserts that the Court's decision to remove § 244(c)(2) results in the statute operating beyond what Congress intended. There is concern that the Court has extended the statute beyond its positive operation as intended by Congress. The court should not modify the meaning of a statute by disregarding an unconstitutional provision. If a provision in a statute is deemed unconstitutional, it does not imply that other provisions in the statute are affected or amplified. The legislative intent can be determined by evaluating all the provisions of the statute, including the unconstitutional provision.