We read all 279 pages of reports about grade changes in Memphis. Here are five big takeaways.

Reports detailing how grades were falsified at Trezevant High School have called into question whether grade changes happening at other Memphis high schools are legitimate.

Shelby County Schools released the results last week of a six-month investigation into how grades are handled at all 41 high schools in Tennessee’s largest district. The probe launched after a new Trezevant principal reported inconsistencies between report cards and transcripts at his school in September 2016.

We read all 279 pages of the reports by legal and accounting firms hired to look into the matter. Here are five takeaways:

1. Some of the allegations have merit.

Complaints that some grades had been changed on transcripts at Trezevant High ring true, according to the report, and there’s cause for suspicion at some other high schools, too.

A team of investigators led by former U.S. attorney Ed Stanton said at least 53 students who graduated from Trezevant shouldn’t have received their diplomas due to improper grade changes.

But Trezevant might not be alone. A separate report by a North Carolina accounting firm found a high rate of grade changes at six other high schools within Shelby County Schools. The average number of grade changes across all high schools was 53, but Trezevant had 461 and Kirby logged 582 between 2012 and 2016. A deeper probe into those schools has been ordered.

2. District leaders weren’t caught totally off guard

While expressing surprise at the findings, district administrators began building in safeguards to prevent illicit grade changes months before Trezevant Principal Ronnie Mackin reported finding discrepancies. Under a 2016 change, Shelby County Schools began requiring all teachers to use the same electronic grading database known as SMS.

“The District implemented this policy in an effort to effectuate a uniform and consistent method for grade entry which was designed to ensure truthful grading data,” the report said. “As an additional safeguard, SCS also required school principals to implement grading protocols aimed at ensuring the accuracy of the grades that teachers entered into SMS.”

Additionally, Mackin told investigators that Superintendent Dorsey Hopson and Chief of Schools Sharon Griffin “informed him that there was an ‘adult culture problem’ and ‘a financial mess’ that needed to be ‘cleaned up’ at Trezevant.”

And this week, Hopson said rumors of grade-changing have been floating around for years.

“As a Memphian, who went to school here, far back as high school, I would always hear rumors of people changing people’s grades,” he told reporters. “That’s persisted for a long period of time.”

3. Grade floors and grade tampering aren’t the same thing.

Around the same time that Mackin turned over evidence of falsified grades, he implemented a “grade floor” policy in which Trezevant students don’t receive grades below a certain threshold.

So if a student was failing a class, Mackin discouraged teachers from giving that student a grade below 60 percent because “there is a mathematical impossibility of scoring high enough to make up the grade in the future,” he wrote in an email to then-supervisor Tonye Smith-McBride. Such low grades would contribute to a lack of student motivation and behavior issues, he argued.

Mackin told investigators that he was referring to future grades, but the timing of his directive appeared to contribute to confusion about grading policies at Trezevant, making some teachers think that their principal was instructing them to retroactively change failing grades to passing ones.

Trezevant isn’t alone in having grade floors. Hopson said other schools have similar practices and that he would like a uniform policy on the issue. Stanton’s report makes that recommendation.

4. Investigators found no evidence to support other complaints that were not about academics.

Mackin’s six-page resignation letter on June 1 accused Shelby County Schools of a cover-up and said that he was being painted as a scapegoat for questionable finances at Trezevant.

“Our investigation has determined that no cover up occurred,” the report read, adding that investigators found no evidence that Mackin was “wrongfully targeted” either as the district looked into finances.

In fact, the report noted that, in several public statements, district leaders hailed Mackin for unearthing suspicious activity on grades. As for a cover-up, Hopson alerted the State Department of Education in a timely matter that the district was conducting an internal review into Mackin’s concerns.

Investigators also found no evidence to support Mackin’s allegations that Trezevant’s football coach mis-reported the school’s enrollment to state athletic officials and that his supervisor had sexually harassed him.

5. There’s still lots of questions to be answered.

The accounting firm hired to review transcript changes at Memphis high schools found that 10 schools had more than 200 instances from 2012 to 2016. However, the review team could not determine if any were fraudulent and concluded that “additional investigation around grade changes is warranted.”

Investigators also were hampered from getting to the truth at Trezevant without the subpoena power that compels witnesses to speak up.

For example, investigators could not locate several people that Mackin claimed had evidence that would incriminate football coach Teli White, who has since been fired, regarding allegations that he paid student-athletes. They also could not search White’s email or bank accounts to look into allegations of financial fraud.

Hopson told reporters this week that his administration is considering turning over a list of former school administrators to Shelby County’s district attorney, who would have subpoena power in the matter. The superintendent, who is an attorney, said the findings of the first external review may merit a criminal investigation.

The full report by Butler Snow & Dixon Hughes Goodman is available here.

The full Ogletree Deakins report is available here.