It was clear Smith fought for her life. Police found a "significant amount" of the suspect's blood at the scene, but without modern DNA testing were not able to make a match in the state database.
That's where Ancestry.com came in to play. Investigators took DNA they collected from the crime scene and sent it to a DNA testing company called Parabon, which found a similar strand of DNA in their system from someone who was trying to uncover their family tree.
They connected the DNA to one of Lee's relatives.
Police got a warrant to get Lee's DNA and traveled to his home in Alabama to collect it.
He was arrested after a match was made this week and brought to Georgia.
"Despite a reward of more than $30,000 and DNA tests conducted on more than 100 individuals over the last 21 years, Police had been unable to positively identify the suspect until this week," Fulton County police officials said in a statement.
Smith worked in marketing and was a youth counselor at Union Christian Church in College Park.
Smith's father said in 2017 interview that he hoped new technology could help police catch his daughter's killer.
James Smith said he found his daughter's body when he went to wake her up for church.
“I opened the door and there she was in her blood on the floor. I thought that was the end of me right there,” James Smith said.
Smith said last year he just wants closure in his daughter's death.
"There's not a day that goes by that I don't think about her," Smith said.
The family issued a statement about the arrest. It reads, in part:
"We have some relief. One chapter has closed, but there are new ones opening with trials, sentencing and all that we will be learning about the next phase of the process."
Police said Lee was 40 years old at the time of the murder and worked at a Georgia jail. It is unclear whether Lee had a connection to Smith or if the murder was random.
"It feels wonderful to finally bring some kind of closure to this family," Lt. Twanesa Howard with the Fulton County Police Department said.