Vance v. Terrazas, 444 U.S. 252 (1980), was a United States Supreme Court decision that established that a United States citizen cannot have his or her citizenship taken away unless he or she has acted with an intent to give up that citizenship. The Supreme Court overturned portions of an act of Congress which had listed various actions and had said that the performance of any of these actions could be taken as conclusive, irrebuttable proof of intent to give up U.S. citizenship. However, the Court ruled that a person's intent to give up citizenship could be established through a standard of preponderance of evidence (i.e., more likely than not) — rejecting an argument that intent to relinquish citizenship could only be found on the basis of clear, convincing and unequivocal evidence.