BISMARCK, N.D. (AP) — A judge in North Dakota has dismissed a felony conspiracy charge against a South Dakota man who prosecutors say was part of the 2016 riot at the Dakota Access pipeline construction site.

Lawrence Malcolm Jr. was charged last year with conspiring to commit criminal mischief based on DNA from a cigarette butt left at the scene. His attorney argued it was impossible to determine where the cigarette butt originated or how long it may have been there.

An affidavit says more than 100 demonstrators halted construction and vandalized equipment on the Standing Rock Indian Reservation.

Malcolm still faces a misdemeanor charge of engaging in a riot.