Hamilton County Prosecutor Joseph Deters, also a Catholic, pursued the death penalty in the Kirkland case and argued that the Vatican stance was misguided.
Fr. Paul Mueller, superior of the Jesuit community at the Vatican observatory, wrote a letter to Deters earlier this month, the Cincinnati Enquirer reported. Mueller and Deters attended the same high school.
"I am disappointed, embarrassed, and scandalized that you, not only a Catholic but also a fellow alumnus of St. Xavier High School, have used the platform of your public office to oppose and confuse the moral teaching of the Church in so open a fashion," Mueller wrote.
"As Prosecutor, you are obliged to enforce civil law. But as a Catholic, you are obliged to endeavor to conform your own mind and heart to the higher moral law and help others in their efforts to do the same – not to undermine their efforts. The teaching of the Church is clear: in defending society against evil, it is morally unacceptable to make use of the evil of the death penalty."
Deters defended his position, saying it was his job to protect society from evil in the world.
According to local media, Deters called Kirkland "a homicidal piece of garbage" who had shown no remorse and would kill more people if he was not executed.
Miller objected to the claim that execution was necessary to prevent Kirkland from further killing.
"It seems unlikely that there is much evidence that this is true," Miller said. He pointed to low prison rates in Ohio, as well as the fact that Kirkland had been in jail for more than nine years without killing anyone during that time.
Kirkland's defense attorney plans to appeal the sentence. The attorney had asked for life in prison without the possibility of parole, arguing that Kirkland had suffered from severe physical, psychological and sexual abuse, as well as mental illness, and should be shown mercy.