The actions of Oxford High School's actions are under a microscope, prompting questions about the Michigan school's responsibility in the fatal shooting of four students and whether there could be legal repercussions for administrators.
Asked if her office was looking into the conduct of school officials, Karen McDonald, the prosecutor, said, "The investigation is ongoing."
First, a teacher found Ethan Crumbley searching online for ammunition. The next day, there was a note on his desk: "The thoughts won't stop. Help me."
School officials met with Crumbley, 15, and his parents, informing them that he needed to begin counseling within 48 hours. After his parents resisted taking him home, administrators allowed him to stay in school.
Shortly afterward, Crumbley fatally shot four students, according to the prosecutor in Oakland County, Mich., who laid out that series of events Friday while announcing involuntary manslaughter charges against the parents.
It was well within the school's rights to require Ethan, who has since pleaded innocent to murder and terrorism charges, to leave campus, said Catherine Ross, a law professor at George Washington University and expert on student rights.
If the parents refused to take Ethan home, it was the legal and ethical responsibility of the school, Ross said, to "remove the student from the classroom and put them in a safe place -- safe for other people and safe for themselves."
School officials have defended their actions. In a videotaped statement posted online Thursday, the superintendent of Oxford Community Schools, Tim Throne, said Ethan had no disciplinary history.
"No discipline was warranted," Throne said. "There are no discipline records at the high school."
But McDonald suggested there were unanswered questions.
When asked whether the school staff should have reported Ethan right away to law enforcement, she said: "Any individual who had the opportunity to stop this tragedy should have done so. The question is what did they know and when did they know it."
A spokesperson for the district did not respond to requests for comment Friday.
Chris Dorn, a school safety consultant with the nonprofit Safe Havens International, said it was advisable for schools to call law enforcement if there was suspicion that a student might be armed.
Dorn has conducted investigations into lapses that led to past school shootings, finding that administrators sometimes worry that calling the police will violate a student's rights. Other times, they have simply failed to take a threat seriously enough.
"Part of it is that people are just generally nonconfrontational," Dorn said. "School staff are often slow to recognize danger because it's not part of their everyday."
While Oxford High School conducted active shooter drills several times per year, "There is a lot of focus on responding to the active shooter, but not necessarily on the prevention for them," he added.
It is historically very challenging to hold a school district legally responsible for a shooting, said Chuck Vergon, a professor of education law at Youngstown State University.
A majority of past school shooting cases featured some kind of warning in advance of potential violence, he said. But it is difficult in most state courts to meet the required standard of proving gross negligence on the part of school officials -- that they acted in "wanton and willful disregard" for the safety or well-being of others, he said.
"That standard has usually shielded school officials in most school shooting cases from civil liability," Vergon said.
But the Oxford school system will most likely face years of litigation over the shooting, if recent history is any guide.
"I definitely think that there's going to be a lawsuit," said Mike Kelly, a lawyer in Northville, Mich., who specializes in representing students who face school expulsion -- including one student who recently faced expulsion by another Michigan district for having a hunting rifle in the car he parked on school grounds.
"There is some culpability and responsibility here on the part of the school," Kelly said.
While school district settlements are not rare, victims' families face obstacles.
This year, schools in Broward County, Fla., reached a $25 million settlement with both survivors and families of the victims of the 2018 shooting at Marjory Stoneman Douglas High School, which left 17 people dead and another 17 wounded. The settlement followed a court decision capping the school system's liability at $300,000 had the victims won at trial.
In the Michigan shooting, a potential lawsuit would probably turn on the question of whether the school took strong enough action to protect students after a teacher happened to see Ethan's drawing, which included a gun, a person who had been shot and a plea for help.
The fact that Ethan was said to have no disciplinary record creates what Kelly called "a gray area" and could become pivotal in any lawsuit claiming the school was culpable because it failed to remove him from campus.