WASHINGTON — Police can use evidence seized during a traffic stop even if it turns out the officers initially pulled a car over based on a misunderstanding of the law, the U.S. Supreme Court ruled Monday. The 8-1 decision written by Chief Justice John G. Roberts Jr. said that such a stop does not violate the Constitution’s protection against unreasonable searches. The ruling came in a North Carolina case in which a police officer pulled over Nicholas Heien’s car because the right brake light was …