Female serial killers may have escaped justice for decades but now they’re making their mark in the city of Washington.
The city has one of the highest murder rates in the nation, and the number of unsolved cases has grown significantly since the late 1990s.
But it may be easier to identify some of the killers than others, and they may have the DNA of a different female victim, according to new research.
“We think they’re just hiding, like, in plain view,” said Katherine Lohr, a University of Washington associate professor who specializes in forensic science.
“They’re just not going to be caught.”
Lohr and her team used DNA samples from about 500 murder victims to try to identify those who could have been the victims of female serial killers.
They looked at samples from women who died in Washington between 1999 and 2005, looking for DNA patterns in the blood, saliva and clothing that might be associated with a female serial killer.
“If they were female, it could be that they were involved in some kind of murder, possibly sexual assault, and it’s really hard to identify the victim,” she said.
The researchers also took into account the types of crimes committed by the victims, and found that there were patterns of the DNA found in both female and male serial killers that were similar.
“That suggests that it’s just a coincidence,” Lohro said.
“The people who committed the murders may have had some kind [of] sexual relationship with the person who did the murder.
So we’ve got a very high correlation between the male and female DNA,” she added.
The research team, which is affiliated with the University of Maryland, said they found that the number and type of crimes a female killer committed varied by age and gender.
“The more a woman kills, the more likely she is to be involved in other crimes, and there’s no clear indication that women are more likely to commit crimes in the absence of a male serial killer,” Loy said.
The research was published in the American Journal of Forensic Sciences.
The female serial killings are more common in rural areas, where more women live, and were often committed by young women who were sexually abused as children, according, Lohrs research.
The researchers found that in a small number of cases, female serial murders may be linked to the sexual abuse of a family member, a neighbor, a friend or a schoolmate.
“There are very few cases that have been documented of male serial murders in the state,” Loyd said.
“And we really don’t know why.”
Lohra, who has studied serial killers since the 1980s, said that the more cases the research team looked at, the less likely it was that they could identify a female murderer.
“When you see something like this, you think, ‘Is it a case of a woman who’s sexually abused, or is it someone who has been sexually abused?’
But it’s more likely that it has to do with something else,” she explained.
“When you do have a case where you can see something, you can identify the suspect.
And it’s a rare case where there’s a strong circumstantial link.”
The new research also highlights the importance of using DNA evidence when identifying a potential suspect in a case, especially when the killer is a woman, and in cases where victims may be related to the suspect’s family, said study co-author Maryam Nasser.
Nasser, who specializes the study of human sexual violence, said there are many reasons why it is important to use DNA evidence.
“We know that there are lots of factors that contribute to how someone acts,” she noted.
“But for us, it’s important to know the specific factor that is influencing her actions.”
Loyd said the research was the result of a collaboration between the University and the Washington State Patrol.
“It was a collaboration with the Washington Police Department, and we’ve been working on this research for almost a decade,” she told ABC News.
“This was a collaborative effort.”LOHR said she was not surprised that the study found that female serial murder victims were more likely than male serial murder suspects to be victims of sexual abuse.
“Women are more prone to sexual abuse, which makes sense,” she concluded.
“Female serial killers are a very small minority of serial murders, and a lot of people don’t believe they are a problem.”