The story we told this week of Michelle Jones, who was imprisoned for killing her son and remade herself into a nationally respected scholar of history, has inspired waves of admiration. It has also drawn a predictable chorus of resentment, posters complaining on social media that a woman convicted of murdering a child gets an education "at taxpayer expense" while so many law-abiding citizens are crushed by student debt. For a moment, let's set aside the discussion of punishment and redemption, the ostensible American faith in second chances, the question of whether it is right to define people by the worst thing they have ever done. Let's talk economics. First, the cost to taxpayers of Jones’s in-state tuition, books and fees at Ball State University would be $43,912 at today’s rates for the four-year degree she earned while incarcerated. The State of Indiana stopped giving financial aid to prisoners in 2011 and killed the college-behind-bars program altogether in 2012, but Jones already had her degree. Read our story, From Prison to Ph.D.: The Redemption and Rejection of Michelle Jones. The real cost to the state of Michelle Jones, however, was her rather atypical off-campus room and board. In Indiana, the cost of incarcerating a prisoner — the construction of prisons, the salaries and benefits of corrections officers, the administrative costs, the terrible food, and often inadequate medical care — is one of the lowest in the country: $14,823 a year, based on 2010 data compiled by the Vera Institute. (The cost in New York is upwards of $60,000.) Jones was sentenced to 50 years. She won parole after almost 21 years. So by earning her parole — in large part through her studies — Jones saved taxpayers $429,867. The number would be bigger if I knew how to adjust for inflation. Consider also that Jones’ education behind bars was actually an investment in her future as a taxpayer. A depressingly high percentage of people released from prison end up homeless, jobless, back in prison, or underemployed. (A Pew Research report calculated that people who have been incarcerated earn at least 40 percent less than those who have not done time.) Instead, if Jones gets her Ph.D. and becomes a history professor, her salary will be in the range of $72,955 to $146,992, according to recent data from Salary.com. If she holds a job at the median salary — $94,124 — for 20 years, and assuming she pays the average 29.8 percent tax on her income, Jones's contribution to federal, state and local government would be $560,979. That’s not even counting consumption taxes such as sales and property taxes. Finally, many wardens and corrections officials will tell you that in-prison education programs help reduce the ambient level of violence and make it easier to retain quality corrections officers, and even to get by with smaller staffs. I can find no way to put a monetary value on this, so I'll toss it in for free. Bottom line: Michelle Jones' transition from prison to Ph.D will be a net benefit to her fellow American taxpayers to the tune of nearly a million dollars — $946,934. That is, of course, a laughably precise number for a back-of-the-envelope calculation. But anyone who looks honestly at the numbers will conclude that Jones’s education — and the many other prison education programs that have survived the tides of resentment — have saved us a bundle. Perhaps we could even invest some of it in relieving student debt. Bill Keller is editor-in-chief of The Marshall Project.