By Alisha Ebrahimji, CNN
(CNN) — Teresa Lee Scalf’s family has searched for the name of the person who killed their loved one for over three decades.
Now, thanks to new DNA analysis, Scalf’s family has an answer – and some semblance of closure – because investigators say they have solved the 1986 murder case.
Donald Douglas, who was 33 at the time, is responsible for Scalf’s death, Polk County Sheriff’s Office said in a news release Monday. Douglas died of natural causes in 2008 at the age of 54, the department said.
Scalf, 29, was the target on October 27, 1986 of a “sexually motivated” attack that ended in her killing in her Lakeland, Florida, home, where she was “severely cut and had significant defensive wounds on her hands,” according to the Polk County Sheriff’s Office.
“He aggressively stabbed her and cut her,” Polk County Sheriff Grady Judd said in a news conference Monday, noting Scalf was nearly decapitated.
In 1986, investigators collected evidence from the crime scene, including blood that did not belong to Scalf, the sheriff’s department said. That sample was submitted and entered into the Combined DNA Index System (CODIS), a database containing DNA profiles from convicted offenders, unsolved crime scene evidence, and missing persons at the local, state and national level.
Douglas didn’t have a criminal history, the sheriff’s office said, and so he did not appear in the system.
Additionally, Douglas’ body was cremated after he died, so his DNA was never obtained by authorities or entered into the database for comparison, according to the sheriff’s office.
In 2022, the sheriff’s office said it partnered with Othram, a Texas-based private lab specializing in forensic genetic genealogy, to analyze the blood sample, the sheriff’s office said.
Othram “analyzed the suspect’s blood and they were able to narrow the scope to distant relatives of the still unknown suspect,” the sheriff’s office said.
Then, detectives followed a trail through a family tree that led them back to Lakeland, and eventually the Douglas family, Brian Bruchey, Polk County Sheriff’s Office spokesperson told CNN Tuesday.
“Eventually detectives narrowed their search down to close relatives of Donald Douglas who lived directly behind Ms. Scalf at the time of her murder,” the sheriff’s office said.
Detectives obtained a DNA sample from a son of Douglas and through a genetic analysis of the DNA confirmed the blood found at the murder scene matched Douglas, according to the sheriff’s office.
“The DNA profile indicated a 100% confidence of a parent/child biological relationship compared to Douglas’ son’s DNA profile,” the office said.
And although the question of “who” killed Scalf has been answered, why she was killed 37 years ago remains a mystery.
‘The most loving person’
Scalf was a nurse and mother whose son was 8 years old at the time, Pam Scalf, one of Teresa’s sisters said.
Scalf’s mother, Betty Scalf, found her daughter’s body the day she was killed, both Judd and the Scalf family said at a news conference on Monday.
Since 911 wasn’t universal yet in 1986, Betty Scalf called police for help after finding a magnet with the police department’s number on the refrigerator at her daughter’s home, Pam Scalf said.
The Scalf family expressed deep gratitude to authorities for pursuing the murder investigation throughout the years. The entire Scalf family works in healthcare due to Teresa, according to Pam Scalf.
“Teresa was a wonderful person, the most loving person,” Pam Scalf said. “She didn’t deserve this. Our family didn’t deserve this.”
“All I want to say is, I’m 84 years old. I lived to see this done,” Betty Scalf said, “I think that’s why I lived so long.”
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CNN’s Chris Boyette contributed to this report.