DENVER - A civil-liberties group plans to provide free representation to a 35-year-old Colorado man who faces criminal prosecution and a jail sentence for giving the finger to a Colorado State Patrol trooper.

The American Civil Liberties Union says the gesture may be rude, but it is protected free speech.

The ACLU says Shane Boor was driving to work in April when he saw a state trooper pull over a car. As Boor passed by, he extended his middle finger in the trooper's direction.

Boor was later stopped and received a criminal summons ordering him to appear in Jefferson County Court to answer a criminal charge of harassment.

The charge carries a penalty of up to six months in jail.