After five weeks of testimony by dozens of witnesses, a DuPage County jury will hear lawyers' final pitch Tuesday before deciding Brian Dugan's fate.
The triple murderer may face execution if jurors agree he deserves to die for the savage 1983 slaying of 10-year-old Jeanine Nicarico of Naperville.
If a unanimous verdict isn't reached, Circuit Judge George Bakalis later will impose a life sentence.
Dugan has been in prison since 1985 serving life terms for two other slayings - those of Donna Schnorr, 27, of Geneva, and 7-year-old Missy Ackerman of Somonauk.
He abducted, raped and killed his three victims, but jurors also were told of a dozen other of his sexual assaults in which the women survived.
Dugan, 53, did not testify before his defense team rested Friday. But the jury heard his words in several hours of taped interviews with law enforcement and mental health experts, dating from the present back to 1985.
Dugan, in a matter-of-fact tone, detailed his violence. The killer said he viewed his victims as objects, rather than real human beings.
He often asked his interviewers to help him understand what was wrong with him. Dugan said his own self-preservation instincts stopped him, though, from seeking psychiatric treatment as a free man.
"I couldn't trust anyone with the knowledge I had of what I had done," he said in a Dec. 5, 1985 interview. "At the time, I thought there was too much to risk."
The seven-woman, five-man jury chose a Naperville Purple Heart veteran as its foreman. The sentencing hearing included 18 days of testimony, plus another two weeks of jury selection.
Prosecutors presented more than 50 witnesses and 400 exhibits, including many graphic crime-scene photos. They argue Dugan is a remorseless psychopath who long ago forfeited his right to live.
The defense team presented several more witnesses to try make its case that mitigating reasons exist to spare Dugan's life. Dugan pleaded guilty, rather than fighting the charges at trial, more than three months ago.
He offered to admit his guilt back in 1985 if prosecutors agreed to spare his life. At the time, two other men were sitting on death row for Jeanine's murder. The defense maintains his cooperation back then was, in part, out of consideration for the wrongly accused men - both of whom were cleared in 1995.
But much of the defense's case involved complex expert testimony regarding functional brain imaging technology as it relates to Dugan's psychopathy.
Dugan scored a 37 out of 40, placing him in the top 99.5 percentile, when the murderer's brain was scanned in psychopathy tests. The average person rates a 4.
Neuroscientist Kent Kiehl said psychopaths such as Dugan share a defect or inactivity in an area of the brain that processes emotion, inhibition, judgment and self-control. Two other defense experts backed up his findings. Scientists haven't figured out what causes psychopathy, be it genetic or societal, but Kiehl said they don't choose to have this brain deficit.
Prosecutors question the reliability of the functional magnetic resonance imaging, or fMRI, technology Kiehl uses in his research with high-security prisoners, especially in a courtroom. In rebuttal testimony, Dr. Jonathon Brodie said Friday that the brain is ever-changing and too complex, while the technology still is too emerging, to draw causal conclusions.
"In 10 years, we'll know more about the brain then we do know," the psychiatrist said. "We will have a better handle on what some of these technologies are telling us."