On Thursday, a judge ruled that the federal case against accused church shooter Dylann Roof failed to thoroughly detail a key element of the shooter’s horrendous crimes.

According to the Charleston Post and Courier, U.S. District Judge Richard Gergel requested that prosecutors submit a “bill of particulars,” detailing 12 of the 33 charges brought against Roof following his June 2015 massacre at Mother Emanuel AME Church. The brutal attack left nine African-American parishioners dead, including the church’s head pastor.

The 22-year-old, who openly professed his views of white supremacy, was indicted on hate crimes, religious freedom violations, and the use of a firearm in a violent crime, the publication reports. He’s also accused of obstructing the practice of religion.

That religious rights charge stood at the center of Thursday’s dispute, as it is the determining factor in Roof’s eligibility for execution. Both state and federal prosecutors are seeking the death penalty for the accused Charleston church shooter.

Per the Post and Courier, defense attorneys for Roof said the federal indictment against their client failed to explain how his crimes were carried out through the use of “interstate commerce.” The small, but significant, detail is a key component in allowing government authorities to indict Roof.

Prosecutors felt they provided enough information about the crimes’ link to interstate commerce by simply stating that Roof’s actions “were in and affected interstate commerce.” Judge Gergel dissented.

According to the publication, Gergel called the commerce connection an “essential element of the offense” and ruled that the indictment “provided no explanation” for the necessary component. He also asserted that the key information was necessary for Roof’s lawyers “to prepare a defense.”

Gergel’s ruling comes almost two weeks after defense attorneys filed a motion to dismiss all federal charges against the accused Charleston gunman. In it, they argued that the federal government didn’t have the constitutional authority to prosecute Roof; instead, the state government should be left to handle the matter, Atlanta Black Star reports. Attorneys also claimed the federal case against Roof violated his 13th Amendment rights (which outlawed slavery) and the Due Process Clause of the Fifth Amendment.

“The charges at issue are extremely grave, but under the Constitution they are not properly charged,” said Sarah Gannett, one of Roof’s lawyers. “The defendant therefore requests that the indictment be dismissed.”

According to South Carolina news station WCSC, jury selection for Roof’s federal trial is set to begin Nov. 7, while his state trial is scheduled for January 17, 2017.