ST. JOHNS (WWJ/AP) – Two teenagers have waived their right to probable cause hearings in the murder of a Michigan State University student, and both have been bargaining with prosecutors about plea deals.

Ninteen-year-old Samantha Grigg and 18-year-old Tyrel Bredernitz waived their right to a preliminary examination Tuesday in a St. Johns courtroom in the murder trial of Dustyn Frolka. A third person charged in the case, 16-year-old Brendon Heim, is undergoing competency proceedings. All three teens are charged with first-degree murder and armed robbery.

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Grigg’s lawyer, Ron Zawacki, said his client is expected to plead guilty to lesser charges April 28. County Prosecutor Chick Sherman said plea negotiations are also underway for Bredernitz.

Frolka, a 19-year-old sophomore from Owosso, was found unconscious Feb. 15 on I-69 in Clinton County’s Bath Township, near Lansing. When officers arrived, Frolka was partially clothed and was in “respiratory distress.” He was rushed to Lansing’s Sparrow Hospital where he was pronounced dead.

Dustyn Frolka (Handout photo)

Dustyn Frolka (Handout photo)

Police said Frolka was beaten with brass knuckles during a robbery and then thrown from a moving vehicle. Prosecutors have said illegal drug money was a motive for the robbery. According to reports, Griggs was driving the SUV while Bredernitz and Heim were beating Frolka.

Officials said all three teens are tied to Saline High School — Grigg is a senior, Bredernitz is a graduate, and Heim is a sophomore dropout. However, their previous relationship with Frolka is unknown.

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Frolka was a talented rapper but “had been on kind of a downward spiral” since the fall, according to fellow hip-hop musician Blake Selby. Selby told reporters that he signed Frolka to the Lansing-based label he runs, though they later parted ways.

MSU police arrested Frolka for cocaine possession on Jan. 31, according to court records. He was then kicked out of his dorm because of actions that were deemed a threat to the safety of other residents, the university said.

According to Frolka’s Twitter page, the student mentioned drug use in the hours before his death, tweeting “I’ve never done DMT and tonight is about to change s***.” DMT acts as an intense hallucinogenic drug when ingested.

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