Nearly six years ago, Heather Vogell and John Perry detected something rather odd.

Heather, the former Atlanta Journal-Constitution investigative reporter who now works for the journalism nonprofit Propublica, was taking a routine look at scores from the CRCT, the state-mandated test intended to measure student performance. John, one of the nation’s leading lights in combining journalism and database analysis, was working with her.

The data suggested that a surprising number of schools had made remarkable gains. Over time, their analysis indicated that some gains were too remarkable – bordering on mathematically impossible. Heather and John found that students in a few Georgia classrooms had improved so much that it made them wonder if the gains were real.

When I was briefed on their early findings at the time, I’m not sure I fully comprehended the enormity of what they had discovered. As we all know, this early inkling began to unravel a scandal that has come to define Atlanta’s failures in the way the 1996 Olympics defined its success. We published their first story in December 2008.

The front-page story came at a time when Atlanta schools were being heralded as an amazing turnaround. Beverly Hall, the Atlanta superintendent, had become an education megastar. Implied in all this success was the sense that someone had at last found the secret formula to the intractable problem of finding academic success in urban classrooms.

As it turned out, the successes were a mirage. We may never know how well the children in Hall’s care were learning.

When we looked at the 2009 scores, we found the same trends and were able to focus more narrowly on Atlanta. Meanwhile, we were hearing from teachers and parents who supported the idea that something was wrong.

As our focus shifted to Atlanta, so did the headwinds. Business leaders - notably some from the Metro Chamber - circled the wagons around Hall and accused us of conducting something on the order of a witch hunt. They argued we were being careless with the city’s reputation as Atlanta struggled to compete in the Great Recession. Some African-American leaders suggested that our reporting hinted at a bias that couldn’t accept that poor black kids could learn.

But the data continued to be consistent and compelling – indicating that the odds were nearly impossible that the changes in test scores could have occurred without human intervention. Moreover, people in APS were providing our reporters clear evidence that something was very wrong.

Our reporting coupled with growing suspicions among state officials eventually grabbed the attention of then-Gov. Sonny Perdue. After we looked deeply at a purported Blue Ribbon study orchestrated by the business community and concluded it was a whitewash, Perdue became furious. When he came to the newspaper for an editorial board meeting, he was as angry as any politician I’ve seen in three decades as a journalist.

In August 2010, he launched a special investigation with the convenient benefit of subpoena power.

State investigators verified our reporting. Moreover, they depicted an administration eager to cover up and loath to confront reality. The investigators depicted a culture where teachers were publicly humiliated or fired for underperformance and whistleblowers were persecuted. “In sum, a culture of fear, intimidation and retaliation permeated the APS system from the highest ranks down,” the report concluded.

On Monday, the final chapter begins. The criminal case comes as the unavoidable conclusion of our reporting and the state’s investigation. After years of maneuvering, 12 defendants remain. Included are high-ranking administrators and classroom teachers. All maintain they had no part in an ugly conspiracy. (Beverly Hall is the 13th remaining defendant; the judge has ruled that she is too gravely ill to stand trial with the others.)

The trial will be painful to watch. The 12 defendants aren’t venal monsters accused of committing crimes that elicit immediate disgust. The criminality alleged here is subtle. All are people who decided on noble and thankless careers as public school educators. Many may have been thinking that test results mattered far less than the good that could come from some good news.

And don’t think that the only people at fault are the ones on trial. The Atlanta cheating scandal could only happen in a community that valued the appearance of success over the hard reality that real progress comes from hard work and patience.

It’s easy to lay blame on Hall and then move along. That’s certainly been a recurring theme when business leaders talk to the newspaper’s leadership. These days some of the folks who told us we were wrong in the beginning now say the AJC has said enough about this scandal and needs to turn the page.

But that’s not what newspapers do. We tell the ugly truths, chronicle the response and then honor the history of what really happened.