Posted: Feb 05, 2016 3:45 PM ESTUpdated: Feb 05, 2016 7:30 PM EST

MONTPELIER, Vt. –An environmental activist is threatening a civil rights lawsuit against Vermont’s attorney general if the office does not drop an investigation of her work.

A complaint from an energy developer led the attorney general to investigate whether Annette Smith is practicing law without a license when she helps neighbors challenge industrial-scale wind projects.

Her lawyer David Sleigh wrote a letter to the AG saying Smith’s work is lawful advocacy and the investigation violates her free speech rights.