The motion was signed by Paul B. Weiss of the law firm Martin & Seibert in Martinsburg, W.Va., and Dwight Sullivan, of the American Civil Liberties Union of Maryland.
Freeman had been holding up a notebook-sized sheet of paper with the words "Washington County Commissioners won't hire black men" written on it when he was arrested by Hagerstown City police officers.
Under the public trespassing statute, anyone refusing to leave a public building or grounds after being asked to do so by an authorized employee of the public agency, in this case County Administrator Rodney M. Shoop, and having "no apparent lawful business to pursue" or "acting in a manner disruptive of and disturbing to the conduct of normal business" can be arrested and charged.
The motion to dismiss says the law is too vague and overbroad to pass constitutional muster.
The statute "is so indefinite that it encourages arbitrary and erratic arrests and convictions," according to the motion.
According to the motion, the statute permits police officers to subjectively "round up the usual suspects," which is "constitutionally indefensible."
Weiss said in an interview that Freeman could have put forth three defenses. One would be to say that no violation of the statute occurred. A second defense would be to maintain that the statute was unconstitutional as it was applied because Freeman was engaging in speech protected by the First Amendment.
The third defense, which is the one presented in the motion, says the statute itself is unconstitutional.
By waiving the first two defenses, Weiss said he intends to use the proceedings as a test case of the statute's constitutionality.
Washington County State's Attorney M. Kenneth Long Jr. would not comment on the case Wednesday.
Freeman said Wednesday he was advised by his lawyers not to comment on the case.
Freeman's case on the charge of trespassing at a public building during business hours is scheduled for Feb. 19 in Washington County District Court.
If convicted, Freeman could face a maximum $1,000 fine and six months in jail.