WICHITA, Kan. (AP) — A judge has spurned a last-ditch effort to throw out before trial the lawsuit against an abortion opponent accused of sending a letter to a Wichita doctor saying someone might place an explosive under her car.

U.S. District Judge J. Thomas Marten on Wednesday rejected claims by anti-abortion activist Angel Dillard that a law guaranteeing access to abortion clinics is unconstitutional. Dillard faces a jury trial May 3 in federal court in Wichita.

The Justice Department sued Dillard in 2011 for sending the letter to Mila Means, who had been training to offer abortions. At the time, no doctor was performing abortions in Wichita in the wake of Dr. George Tiller’s murder.

Marten also ruled on what evidence jurors will hear to determine whether Dillard’s letter constituted a “true threat.”