In politics, a defector is a person who gives up allegiance to one state or political entity in exchange for allegiance to another. The term is sometimes used as a synonym for traitor, especially if the defector brings with him secrets or confidential information. More broadly, it involves abandoning a person, cause or doctrine to whom or to which one is bound by some tie, as of allegiance or duty.
International politics
.]]The physical act of defection is usually in a manner which violates the laws of the nation or political entity from which the person is seeking to depart. By contrast, mere changes in citizenship, or working with allied militia, usually does not violate any law.For example, in the 1950s, East Germans were increasingly prohibited from traveling to the Western Federal Republic of Germany where they were automatically regarded as citizens according to Exclusive mandate. The Berlin Wall and fortifications along the Inner German border were erected by the socialist Eas
Source:
http://en.wikipedia.org/wiki/Defector