Jeffrey Willis will stand trial on open murder and kidnapping charges in the Jessica Heeringa case.

A Muskegon County judge decided there was enough evidence to have a trial after four days of testimony in the preliminary hearing. It also comes more than three and a half years after Heeringa disappeared from the Exxon gas station she worked.

On Tuesday, Dec. 13, the defense attorney questioned the investigative process, asking why it took 13 months to write a police report after Heeringa's disappearance.

The defense also asked the lead investigator how other people questioned early in the case were ruled out as suspects. A close friend of Heeringa testified that Jessica was a "party girl" and that they did drugs together.

Earlier: Scratches, computer files part of day three at a preliminary for Jeffrey Willis

Before issuing his ruling to move the case to trial, Judge Raymond Kostrzewa highlighted evidence such as the file on Willis' computer titled "vics" which prosecutors say included photos of Heeringa, her initials and the date she disappeared.

Another computer file had similar items for Rebekah Bletsch. She was shot and killed while jogging in 2014. Willis will stand trial for Bletsch's murder in 2017.

Related: Teenage victim in Jeffrey Willis case testifies: 'I yelled' don't kill me

The judge explained his decision by saying, "The totality of evidence convinces me, certainly for probably cause purposes, that Mr. Jeffery Thomas Willis should be bound over to circuit court, on the charges of open murder and on the charge of kidnapping.

"I'm finding that neither of those criminal offenses are cognizable in the district court, therefore this court is duty bound to bind the case over to trial in circuit court."

Willis remains in the Muskegon County Jail, after Kostrzewa denied bond.

Related: Jessica Heeringa customer: 'Something wasn't right' when Willis spoke up