As she sat in a Franklin County courtroom and contemplated a possible death sentence for the man who killed her father, Dionna Kiernan expected to hear something about his background that would explain the crime. Instead, a parade of character witnesses spoke about Daniel Teitelbaum last week as a brilliant, highly educated man whose life has so much value that he shouldn't be put to death for murdering his business partner, Paul Horn.

As she sat in a Franklin County courtroom and contemplated a possible death sentence for the man who killed her father, Dionna Kiernan expected to hear something about his background that would explain the crime.

Instead, a parade of character witnesses spoke about Daniel Teitelbaum last week as a brilliant, highly educated man whose life has so much value that he shouldn�t be put to death for murdering his business partner, Paul Horn.

A photo of Teitelbaum napping peacefully with his infant son on his chest was projected on a screen in the courtroom as defense attorney Adam Nemann made his closing argument to jurors.

The Common Pleas Court jury weighed the information, known as mitigation, against the aggravating circumstances of the crime and recommended a sentence of life in prison with no chance of parole. Judge Charles Schneider is scheduled to impose the sentence today.

Kiernan didn�t anticipate a death sentence, which no Franklin County jury has recommended since 2003, but she was taken aback by all the positive information presented about Teitelbaum.

�There was no mitigating factor,� she said. �This person had every privilege in the world.�

Assistant County Prosecutor Marla Farbacher took a similar position in her closing argument to the jury, asking, �What could possibly be mitigating about coming from a loving family, having a good education and a son that you care about?�

But according to experts on the topic, there�s virtually no limit to what jurors can consider as mitigation in reaching what must be a unanimous decision for life or death.

�You hope to present something that will cause at least one juror to see your client as a person they don�t want to put to death,� said Dorian Hall, supervisor of mitigation and criminal investigations for the Ohio public defender�s office.

The Ohio Revised Code requires jurors to consider �the history, character and background of the offender� and lists several factors that can be taken into account, including the lack of a significant criminal record and whether a �mental disease or defect� contributed to the offense. Beyond that, the law gives defendants �great latitude� in presenting �any other factors that are relevant to the issue of whether the offender should be sentenced to death.�

�Mitigation is not an excuse or a justification for the crime,� said Gerald Simmons, a Columbus defense attorney who began handling death-penalty cases in the 1970s. �It�s any reason a juror chooses to not impose the most-severe penalty.�

The typical defendants in capital murder cases are poorly educated and had difficult or abusive childhoods and a history of mental-health problems. Those factors are commonly presented as mitigation in the sentencing phase of death-penalty cases.

Teitelbaum, 47, of Margate City, N.J., is not a typical death-penalty defendant. He has a doctorate in engineering and public policy from Carnegie Mellon University in Pittsburgh. His father and stepmother were psychology professors at the University of Florida and co-wrote a book on autism.

The friends and former colleagues who came from across North America last week to testify on Teitelbaum�s behalf included a University of British Columbia professor who supervised his doctoral thesis and a high-school buddy now serving as dean of liberal arts at the University of Louisiana-Lafayette.

Mary Burdette of Fort Worth, Texas, who served as the mitigation specialist for Teitelbaum�s defense team, said she took offense at the prosecution�s suggestion that the information presented did not qualify as mitigation.

�The object is to humanize the defendant, make the jury realize there is more to the defendant than just the events of one day,� she said. �The purpose is to show that this is a person of value, that his life has meaning.�

Kiernan, who lives in Manassas, Va., was thinking about the life that was lost. Horn, who had raised her from age 8 after her mother married him in 1986, was murdered at age 54 on March 10, 2011. His bullet-riddled body was found on the floor of his Grove City apartment in the midst of a business dispute with Teitelbaum, his partner in a private poker club in Grove City.

Evidence showed that Teitelbaum plotted the murder for months and even tried to hire a friend to commit the crime.

�From our standpoint � the victim�s family � to listen to what a great guy (Teitelbaum) was, you think, �What about the person who died?�?� she said. �I understand why it�s done, but it doesn�t make it any easier to tolerate.�

jfutty@dispatch.com