term:

Insurgent

insurgent n

1 : a person who rises in revolt against civil authority or an established government
;esp
: one not recognized as a belligerent
2 : one that acts contrary to the established leadership (as of a political party, union, or corporation) or its decisions and policies
adj : rising in opposition to civil or political authority or against an established government

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.