DETROIT — Independent investigators on Monday concluded that the Oxford High School shooting in Michigan that killed four students and injured seven others on Nov. 30, 2021, was avoidable, had the district followed the threat assessment policy.

Investigators noted in a 572-page report that "individuals at every level" in Oxford Community Schools — including the district's former Superintendent Timothy Throne, the school board and administrators — failed to provide a safe and secure environment for students.

Ethan Crumbley, who was 15 at the time of the massacre, pleaded guilty to all his crimes and is scheduled to be sentenced on Dec. 8. He faces a life sentence without the possibility of parole. The Crumbleys, who bought their son the gun used in the rampage, are the first parents in America charged in a mass school shooting.

In the report, led by Guidepost Solutions, investigators said the shooter should have been sent home on Nov. 30, after counselors called his parents in for a meeting over behavioral concerns. Instead, he was allowed to return to class.

"Our investigation has revealed that had proper threat assessment guidelines been in place and District threat assessment policy followed, this tragedy was avoidable," the report reads.

The investigative firm was hired by Oxford Community Schools' board in 2022 following an outcry from the community about school safety and lingering concerns over what district officials knew about disturbing behavior exhibited by the shooter before he killed four students and injured six students and a teacher. Several school board members have since resigned and similarly have questioned the district's transparency around the shooting.

Tate Myre, Hana St. Juliana, Madisyn Baldwin, and Justin Shilling were the four students who died in the attack.

Read the report here:

Shortfalls in threat and suicide assessment

The report called out school administrators for failures involving the district's threat assessment process. Threat assessments conducted on students typically examine whether a student poses a danger to themselves or others.

Investigators said the district had adopted threat assessment policies, but a review found that there were significant shortfalls in executing these policies in Oxford. The report said Throne was responsible for creating such guidelines, and the school board should have ensured policies were implemented.

The report notes that Throne failed to make it evident which district administrators were responsible for threat assessments, so much so that two school administrators in the report, then-Assistant Superintendent Jill Lemond and then-Assistant Superintendent Ken Weaver, said that they believed the other was responsible for the assessments.

"We found that OHS administrators, faculty, and staff were unaware of the District’s threat assessment policy or the District’s threat assessment form," the report reads. "That is a significant failure, one that rests primarily with Superintendent Throne, who as the District’s chief executive officer is ultimately responsible for ensuring that building-level administrators know about and are following the District’s policies."

Throne could not be immediately reached for comment.

The report also states that the shooter should have been assessed under suicide intervention protocol, and that counselor Shawn Hopkins and dean Nicholas Ejak should have elevated concerns about the shooter to Oxford High's administration.

Ejak and Hopkins could also not be immediately reached for comment.

In addition, the report found no one was monitoring the more than 90 security cameras around the school and its grounds so staffers were not able to "broadcast ongoing messaging regarding the shooter’s location and movements" to students and staff in the school, which is protocol for active shooter situations.

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Shooter told classmates it was the 'last day of school'

Hopkins testified that on Nov. 30, he checked the school's attendance system to make sure that Crumbley was marked as present in his class and lunch because he wanted to make sure Crumbley was never alone, according to the report.

The report adds that police were informed that Crumbley had told another student in that class, "Don't worry, it is the last day of school." There's no evidence that any student who heard this reported it to school officials, and the report stresses that all students mentioned in the report were children.

"Again, we emphasize that these students are not responsible in any way for what happened on November 30, 2021," the report states. "While students can be a valuable source of information about potential threats, it is not the responsibility of school-age children to prevent school shootings."

Many didn't cooperate with investigation

Guidepost reached out to 143 current or former Oxford Community Schools employees, but only 51 were interviewed, according to the report. Many denied interview requests or did not respond, which Guidepost attributes to concern about ongoing lawsuits connected to the shooting.

Guidepost asked the district to require employees to participate, but the district refused. The investigators specifically called out seven district employees who were not interviewed for the investigation but played a crucial role in the events surrounding the shooting, including Hopkins, Ejak, and other Oxford High employees.

While some school district employees declined interviews, family members of all four victims and some students who survived the shooting sat down with investigators, according to the report.

Families told investigators that they were disappointed by the transparency and support they received from the district.

First parents charged in a U.S. school mass shooting

With their involuntary manslaughter trial 11 weeks away, the Crumbleys' defense strategy is being called into question. The parents each have their own lawyer but have mounted a joint defense since their arrests. 

In a series of back-and-forth emails, prosecutors raised that they had new reasons to believe a conflict issue remains and must be addressed to avoid a potential mistrial. The prosecutor cited, among other reasons for this concern, communications that Jennifer Crumbley has had in jail in which she blamed her husband — though he did not elaborate further.

The defense accused the prosecution of trying to make it look like the Crumbleys were not on the same page. 

"The obvious goal of the prosecution at this point is to try to create a rift between the defendants and defense counsel and to make it appear to the public … that the Crumbleys are not united. This could not be more untrue," defense attorney Shannon Smith wrote in a filing Friday.

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Contributing: Tresa Baldas, Detroit Free Press