The latest high-tech gadgets bring promises of convenience and efficiency, with the hopes of enhancing our lives and making our jobs easier. But sometimes they create new challenges. For example, technological advances have helped law enforcement in their fight against crime. But one device is raising concerns from civil liberties groups who claim its use violates the constitutional rights of motorists who carry cell phones during routine traffic stops. And data suggests that this could pose an even greater threat to the privacy rights of blacks and Latinos, who are more likely to be stopped by police.