Prescott (via Mugshots.com)

A judge in Prince George’s County dismissed charges against a man who was arrested last year after allegedly telling a co-worker that he was planning on carrying out a workplace shooting.

Neil Edwin Prescott, a Crofton, Md. resident, was charged last July with telephone misuse stemming from a call in which he threatened his employer, a paper services contractor in Prince George’s County. During the call, authorities said Prescott referred to himself as a “joker,” a possible reference to a Batman villain. The phone call took place just days after a gunman in Aurora, Colo. walked into a movie theater screening The Dark Knight Rises and opened fire, killing 12 and wounding 50.

Police who searched Prescott’s home last year found a weapons cache including 20 guns and more than 400 rounds of ammunition. At the time of the search Prescott was reportedly wearing a shirt with the phrase “Guns don’t kill people, I do.”

But in court today, Judge Patrice E. Lewis said that prosecutors did not properly specify the crime they were accusing Prescott of carrying out, according to The Baltimore Sun. Though prosecutors dispute the Lewis’ decision:

Prince George’s County State’s Attorney Angela D. Alsobrooks said her office will review whether to refile charges. She said her office didn’t make a mistake with the charging document. Alsobrooks believes prosecutors followed state statutes closely when it accused Prescott of the crime.

Prosecutors on Prescott’s case acknowledge that his collection of guns was obtained legally. Maryland recently adopted some of the strictest gun control laws in the United States, which Gov. Martin O’Malley proposed in response to the Aurora shooting and other mass killings last year.