In 1967, in Afroyim vs. Rusk, the Supreme Court held that Congress cannot strip individuals of citizenship unless they choose to renounce it. In words directly applicable to the Lieberman proposal, the court stated: “Citizenship is no light trifle to be jeopardized any moment Congress decides to do so…. The very nature of our free government makes it completely incongruous to have a rule of law under which a group of citizens temporarily in office can deprive another group of citizens of their citizenship.”
Nor can Congress eliminate the need to inform terrorism suspects of their right to remain silent. The Supreme Court has held that the warning is required by the privilege against self-incrimination found in the 5th Amendment. Previous efforts by Congress to eliminate or modify this have been declared unconstitutional.
Moreover, such actions are unnecessary. Those who commit terrorist acts can and should be severely punished; stripping them of their citizenship and failing to inform them of their right to remain silent serve no additional purpose.