(NewsNation) —  The parents of a 15-year-old charged with a shooting rampage at a Michigan high school could call their son to testify in their own case.

James and Jennifer Crumbley both face four counts of involuntary manslaughter after their son Ethan allegedly shot and killed four students and injured seven others at Oxford High School in November.

The intention to call their son to the stand recently shocked the courtroom. Prosecutors argue the defense will use Ethan Crumbley to downplay the role of his parents.

Rachel Fiset is a criminal defense attorney. While appearing Tuesday on “NewsNation Prime,” she said she doesn’t buy that the defense claims to not be trying to throw Ethan Crumbley under the bus to save the parents.

“Don’t buy it,” Fiset said. “I also don’t think that Ethan, if he’s advised by counsel, will in any way testify as the Fifth Amendment covers a whole host of things that could be incriminating there. … It’s hard to believe that there’s anything that he could go up and say that would not possibly be used against him in his own legal action.”

Fiset also believes there’s not much Ethan Crumbley could say that could potentially help his parents.

“I think they want him there. They want his presence there. They want to point to the real shooter at some point in their legal argument and take the responsibility away from these parents,” Fiset said.

Fiset explained that typically a judge would not get involved in the decision of whether or not Ethan Crumbley would testify, but pointed out that if Crumbley’s mental capacity is still in question, he should not take the stand.

While the prosecutors have a tough case on their hands, Ethan Crumbley’s journal is expected to be a major point of contention. In the journal, he says he wants help but his parents do not listen.

“That journal is incredibly critical,” Fiset said. “The prosecution might want him in there, so they can say it’s not hearsay but that it is a credible statement of ‘I am asking my parents for help and they are not giving it to me. But instead they are giving me ammo and guns.’ I mean, that journal is a huge piece of evidence.”

The trial for the parents is set for October. Ethan Crumbley’s trial is slated for January of next year.