A district judge dismissed a murder charge Monday against a Billings woman accused of shooting a Wyoming man, saying state prosecutors violated the defendant's right to a speedy trial.

Bianca Wilson was charged with deliberate homicide for the September 2004 shooting of 30-year-old Justin Marchant, of Cowley, Wyo. Judge Blair Jones ruled Monday that prosecutors could not refile the charge.

Wilson was first charged with Marchant's murder Sept. 17, 2004, three days after his body was found on a rural road just north of the Wyoming border. The charge was dismissed for the first time in April 2005 at the request of state prosecutors, who said they did not have enough evidence to convict Wilson.

On the day the murder charge was dismissed, Wilson and co-defendant Jesus Villarreal Jr. were charged with felony tampering for allegedly hiding and cleaning blood from the car where Marchant was shot.

Wilson was convicted on the tampering charge and was sentenced to five years in the Montana Women's Prison, where she continues to serve her sentence. The tampering case against Villarreal was dismissed after a judge declared a mistrial.

Assistant Attorney General Barbara Harris, who could not be reached for comment Monday afternoon, refiled the murder charge against Wilson in May 2008, saying new evidence had surfaced to justify the prosecution.

Jones said in Monday's ruling that state officials delivered 600 pages of crime lab evidence to Wilson's attorneys days before her trial was set to begin in December. A new trial date was set for April to allow Wilson's attorneys time to review the records.

Jones criticized prosecutors for failing to provide Wilson's defense team with evidence they needed to review before trial, and faulted them for delaying the trial for 548 days.

Generally, state law requires a review of a speedy trial violation if the case has been pending for more than 200 days if the defendant hasn't waived his or her right to a speedy trial.