CNN
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The Michigan Supreme Court has delayed the start of the involuntary manslaughter trial of Jennifer and James Crumbley, the parents of Oxford High School shooter Ethan Crumbley, so their appeals can be heard by a lower court.

In the order issued Tuesday, the court sent both parents’ cases to the Court of Appeals for the state to consider “whether there was sufficient evidence of causation to bind the defendants over for trial on the charges of involuntary manslaughter.”

The case stems from the mass shooting almost exactly a year ago in which Ethan Crumbley, 15 at the time, killed four students and injured six students and a teacher at his high school. He pleaded guilty last month to terrorism and murder charges and faces up to life in prison without parole.

In an unusual move, prosecutors arrested his parents and accused them of giving their son easy access to a firearm and disregarding signs he was a threat. They were arrested days after the shooting in a Detroit warehouse following a manhunt after they failed to come to court for their initial arraignment.

James and Jennifer Crumbley have pleaded not guilty to four counts of involuntary manslaughter and have argued that the charges have no legal justification and the couple should not be held responsible for their son’s killings.

The case has unfolded as the scourge of US campus shootings has continued, with more than 70 recorded this year on US school grounds, including three University of Virginia students shot dead this month on a bus returning from a field trip and 19 fourth-graders fatally wounded six months ago in their Texas classrooms.

At a preliminary hearing in February, a judge ruled there was enough evidence to proceed to trial, which had been set to begin in January.

The trial is now stayed pending completion of the appeals, the order said.

In a dissenting opinion, Justice Richard Bernstein wrote while the case raises novel issues, prosecutors presented sufficient evidence and addressing these legal issues at this stage will “unnecessarily delay the trial proceedings.”

CNN legal analyst Paul Callan said the court’s order postponing the trial is “highly unusual,” noting that courts customarily wait until court proceedings have concluded.

“The ‘causation’ issue in a criminal case is usually determined by a jury after hearing live witnesses in open court rather than by a panel of appellate judges,” he said. The order, he continued, suggests a majority of judges have “serious concerns” that the parents’ roles “may not be adequate to establish legal ‘causation’” in their son’s killings.

The evidentiary hearings earlier this year included testimony from a detective who said he found text messages from Ethan Crumbley to a friend saying he was having hallucinations and hearing voices and had asked his parents to take him to a doctor. According to the messages, Ethan said his father gave him pills and told him to “suck it up,” and his mother laughed at him, the detective testified.

“They make me feel like I’m the problem,” Ethan Crumbley texted. “My mom makes everyone feel like a piece of sh*t.”

Still, the detective acknowledged there were no text messages between the parents about concerns he would hurt anyone and no evidence they were aware of his plan to attack a school.

“In the grand scheme of all of the messages (between Ethan and his friend) … there is nothing to indicate that Jennifer or James were told or were aware of a plan to commit a school shooting like what happened at Oxford High School on 11/30?” the defense asked the detective.

“Correct,” he answered.