A Colorado high school student has defied a court ruling on wearing a Mexican and American flag sash at graduation ... with her attorneys saying their ban on her sash violated free speech and ...

He told her that because Kayleigh wore a Mexican heritage sash at her graduation this past May ... the attention of the League of United Latin American Citizens (LULAC), a civil rights organization.

Her lawsuit follows another in Colorado, where a student sued for not being allowed to wear her Mexican ... a sash composed of symbols from the American and Mexican flags during her graduation ...