my witness. I signaled for Mattie to go out to the witness room to wait for her turn to testify, and I called Mike’s name into the record.
Mike Chapman walked to the stand and placed his hand on the Bible that the court officer held out to him. I walked him through his education at Fordham College, where he majored in military history, through his years on the job and early successes that vaulted him to the prestigious homicide squad, and brought him to the current re- investigation of Kayesha Avon’s death.
“Did you respond to the scene of the crime, Detective?”
“Yes, ma’am, I did.”
“At what location?”
Mike stated the address. “On the rooftop of her apartment building, in the projects at Taft Houses in East Harlem.”
I let him describe the heartbreaking sight of the college student’s body, after she was abducted from the elevator in her own building on her way home from class.
“Were you present the following day, eight years ago, at Ms. Avon’s autopsy?”
“Yes, I was.”
“What findings were made by the pathologist?”
“There were six stab wounds in Kayesha’s neck and chest, one of which pierced her heart.”
“Was there any blood evidence found at the scene?”
“No. No, there was not.”
“Any fingerprints?”
“None.”
“Any seminal fluid?” I continued.
“Yes. There was semen in her vaginal vault, and also on her right thigh. She appeared to have been sexually assaulted before she was killed.”
“Was a genetic profile developed by a forensic biologist at the Office of the Chief Medical Examiner?”
“Yes, ma’am.”
“Can you tell us what efforts were made at that time to find a match to that DNA sample?”
“As Your Honor knows,” Mike said, “back then, we were in the infancy of databanking. We ran the crime scene samples against the entries-many thousand fewer than there are today-and had the lab make comparisons to specific suspects we developed through the tip hotline.”
“Was a match ever declared?” I asked.
“Nope. Not even close.”
“What else did you do?”
“Every six months, I asked Dr. Prinzer at OCME to run the evidence against the convicted offender databank, which has been growing steadily, Judge. Kept going back, hoping to get lucky.”
Mike had been haunted by the brutality of Kayesha Avon’s death. He had refused to give up the investigation to the more recently formed cold-case squad, determined to find the young girl’s killer himself, with the help of this revolutionary scientific technique.
“Was Jamal Griggs’s DNA profile among the samples submitted during the last seven and a half years, Detective?” I asked.
“No, ma’am.”
“Is it correct that Jamal Griggs had a homicide conviction?”
“Yes, he did. But because he had been a juvenile offender at the time of the murder, his DNA was not included in the databank.”
“Do you know the facts of that case?”
“Yeah. I do.” Mike paused and stared directly at Griggs. “Jamal was fourteen years old. He had dropped out of school to sell drugs with his big brother, Wesley.”
Eli Fine pushed his chair back but seemed uncertain about whether he should be objecting to this line of questioning.
“The girl he killed was sixteen,” Mike went on. “Jamal stabbed her in the back when she made the mistake of accidentally busting up a drug sale by knocking on the wrong door.”
“Did there come a time when you asked Dr. Prinzer for a comparison to be made to Mr. Griggs’s DNA?”
Mike shifted in his seat and ran his fingers through his hair. “Yeah, about three months ago, just after his robbery conviction.”
“Would you tell the court what result you were given?”
“Objection, Your Honor.”
“On your feet, Mr. Fine,” Moffett said. “That’s the only way I can overrule you. What grounds?”
“Hearsay.”
“You’re not offering this for the truth of it, are you, Alex? Dr. Prinzer’s going to testify, too, isn’t she?” Moffett asked, without waiting for my answers. “Overruled. It’s just a hearing, young man. You got no jury. Save your energy for cross-examination.”
Fine sat down and scribbled furiously on his legal pad while Mike answered the question. “There was no hit, Ms. Cooper, but Dr. Prinzer told me she had a partial match.”
I finished questioning Mike, establishing that every other means of identifying the perpetrator in Kayesha’s homicide had been unsuccessful. Moffett needed to understand that a kinship search was our only alternative. Fine went nowhere with his brief cross-examination, and Mike stepped down from the stand.
“The People call Dr. Mathilde Prinzer,” I said. She would take the scientific piece of the testimony forward.
It took more than fifteen minutes to list her credentials and establish her unique expertise in this still-evolving field of forensic science. If this case of first impression was to stand up to appellate scrutiny, I wanted the full effect of this brilliant scientist’s body of work.
In addition to her daily routine with the five city prosecutors’ offices and the NYPD, Mattie had been among the OCME heroes of 9/11, working doggedly with her colleagues to identify victims from thousands of tiny fragments of human tissue.
I ran her through a primer of DNA testing, more familiar to Moffett than to Fine, who had a puzzled look on his face throughout the entire direct.
“When you compare a suspect’s DNA profile to a crime scene evidence sample, Doctor, what are the possible outcomes?”
“Traditionally, Ms. Cooper, we have had three results. A match can be declared if you have thirteen loci in common-that is, thirteen places on the chromosome at which the gene for a particular trait resides,” Prinzer said, speaking slowly and looking at Fine as she spoke. “A suspect can also definitively be excluded if genetic differences are observed. The third option has been a finding of ‘inconclusive’ if we don’t have enough information to make a positive determination.”
“Has the scientific community recently accepted a fourth category?”
“Yes. We have begun to develop indirect genetic kinship analyses, using the DNA of biological relatives, in humanitarian mass disasters and for missing person identifications, situations in which we have only small samples of genetic material. We try to compare those to DNA from surviving relatives. In those instances, we’re usually working with partial matches.”
“Can you explain to the court the meaning of the term ‘partial match’?”
Moffett moved his chair closer to Prinzer.
“Certainly. When we look at the thirteen loci needed to declare a match, there are two physical traits charted at every one of them. You see them as peaks on the Avon case lab report Ms. Cooper provided to you,” she said, as Moffett and Fine tried to find the corresponding page. “These peaks-or alleles, as we call them-come in pairs, one from the mother and one from the father.”
Moffett nodded as he listened.
“In a partial match, at each of the thirteen critical loci, the profiles being compared have at least one allele in common.”
“You could see that on this paper?” the judge asked, bending over the bench and holding out his report to Mattie.
