Daniel Wells arrested after police match discarded cigarette butt with evidence left at crime scene. Photo / AP
Daniel Wells arrested after police match discarded cigarette butt with evidence left at crime scene. Photo / AP
Daniel Wells accused of murdering Tonya McKinley after police use genetic genealogy to identify suspect with DNA commercial databases.
DNA evidence found on a discarded cigarette has led to the arrest of a US man suspected of murdering a woman 35 years ago.
Daniel Wells, 57, has been charged inPensacola, Florida with the murder of Tonya McKinley, 23, who was strangled and sexually assaulted on New Year's Day 1985.
Generations of detectives in Pensacola had tried to solve the case without success.
"Despite having a good bit of physical evidence and dozens of interviews, over time, the trail went cold.," the Pensacola Police Department wrote on Facebook.
"It seems that every couple of years a new lead would pop up and we would drop everything to run it down. We did this time and time again."
Daniel Wells arrested after police match discarded cigarette butt with evidence left at crime scene. Photo / AP
Police arrested the suspect thanks to a technique known as "genetic genealogy" in which police have matched DNA evidence left at the original crime scene with samples sent to commercial ancestry databases.
These databases are filled by people wanting to know more about their ethnic origin or track down long-lost relatives.
Police forces are enlisting the help of "genealogy detectives" to compile family trees and identify potential suspects.
Once identified, the suspect is discreetly followed by police in the hope that the individual will discard something which will give them a DNA sample to match against that found at the original crime scene.
In the case of Wells, it was a cigarette butt, which he threw out of his car.
The first trial in which the technique was in June last year when William Earl Talbott II was found guilty of a 1987 double murder in Washington State.
Police forces in the US estimate that genetic genealogy could help crack an estimated 100,000 cold cases across the country. Some have raised ethical concerns about using DNA supplied voluntarily to ancestry websites for crime detection.
Ms McKinley's son, Timothy Davidson Jr who was a baby at the time of the murder, hailed the breakthrough.
