DNA, the human genetic blueprint as individual as a fingerprint, will come into play this week in one of only several death-penalty cases involving such evidence to reach a Maryland court.
The case, in which an Aberdeen man is accused of robbery, kidnapping, attempted rape and first-degree murder in the fatal stabbing of an Aberdeen Proving Ground soldier, is one of a growing number in which prosecutors use analyses of DNA in their efforts to link defendants to victims.
About 25 criminal cases in Maryland involving such evidence have come to trial in the past several years. Another 100 or so are pending.
"The first thing a defense attorney wants to know is 'Do you have DNA evidence?' " said Robert L. Dean, an assistant state's attorney for Montgomery County who has conducted extensive research on the subject. He said the increasing use of DNA evidence is resulting in more guilty pleas.
Many defense attorneys still are quick to challenge the reliability of the DNA "fingerprinting" technique, Dean said. "They are also quick to embrace it when we free their clients" after DNA in blood, semen or tissue fails to link a suspect to a victim, he added.
Defense attorneys in the Harford County case -- being heard in Baltimore County Circuit Court due to pretrial publicity -- say they will challenge the reliability of DNA evidence in pretrial motions.
"It is clear that the forensic process is still in its infancy and cannot be unquestionably accepted by courts in criminal cases," the defense attorneys wrote in court papers. "This is especially so when, as here, the ultimate question is one of capital sentencing."
An analysis of DNA, or deoxyribonucleic acid, from blood, semen or tissue can determine the identity of the person from whom it came. Except for identical twins, each person's molecular structure of DNA, the substance in cells that determines genetic makeup, is believed to be unique.
The victim in the Harford case, Spec. 4 Bonnie Sue Joseph, 21, was a clerk in the 523rd Military Police Company at Aberdeen Proving Ground.
Joseph's body was found March 12, 1990, in Edgewood in a field near the 1200 block of Van Bibber Road. Joseph had left the proving ground, where she was working the night shift, at about 2 a.m. that day to buy food for her and her co-workers.
Prosecutors say the defendant, Daniel Eugene Turner, 32, abducted the woman from a 7-Eleven store on U.S. 40 in Aberdeen. He then robbed her, attempted to rape her and stabbed her 25 times in the head, chest, abdomen and back, the prosecutors allege.
Joseph I. Cassilly, the Harford state's attorney, is seeking the death penalty for Turner, a one-time circus laborer in Baltimore and New York.
A conviction of first-degree murder and any one of the kidnapping, robbery or attempted rape charges would allow Cassilly to proceed with a separate sentencing proceeding seeking the death penalty.
Cassilly and M. Teresa Garland, an assistant state's attorney also prosecuting Turner, say they intend to present FBI analyses DNA taken from semen found on Joseph's clothes and blood found on Turner's clothes at the time of his arrest, which occurred several hours after the victim's body was found.