(NewsNation) — A grand jury has indicted Bryan Kohberger in connection to the killings of four University of Idaho college students. The indictment allows prosecutors to skip a preliminary hearing that had been scheduled for June.

Without a grand jury indictment, the preliminary hearing would have allowed the defense to poke holes in the prosecution’s case, explained NewsNation legal contributor Sara Azari.

“The defense would essentially participate in that (preliminary hearing), they could bring their own witnesses to impeach prosecution witnesses,” Azari said.

Kohberger — a 28-year-old graduate student studying criminal justice at Washington State University — had already been charged with burglary and four counts of first-degree murder for the stabbings of Xana Kernodle, Ethan Chapin, Madison Mogen and Kaylee Goncalves.

The new indictment includes those same charges and means there’s enough evidence for the case to move forward. Kohberger is set to appear for arraignment on Monday, May 22, where he will enter a plea.

Instead of the preliminary hearing, prosecutors chose to present the case to a grand jury — proceedings that tend to be secretive and don’t involve the defense. That process allows prosecutors to avoid certain challenges by the defense.

Even though the defense doesn’t participate, prosecutors are still required to provide exculpatory evidence for the grand jury to consider.

“You have to still represent the evidence that is perhaps favorable to the defense,” said Azari. “You can’t just go in there with all the receipts and incriminating evidence.”

Court documents have already revealed some of the evidence prosecutors are likely to present if the case goes to trial.

Authorities identified Kohberger through a combination of DNA evidence at the crime scene, cell phone records and his vehicle, according to a probable cause affidavit released in January.

The 28-year-old was arrested Dec. 30, 2022, at his parents’ home in eastern Pennsylvania, where law enforcement officials seized dark clothing, medical gloves, a flashlight and other items.

Investigators also recovered stained bedding and strains of hair at Kohberger’s apartment in Pullman, Washington, according to a separate search warrant.

It’s still unclear what may have driven Kohberger to commit the crime or whether he specifically targeted any of the victims.