The Jameis Winston sexual assault case has taken a couple of ugly turns this week. The biggest news is that DNA taken from the underwear of the woman claiming a sexual assault occurred matches the DNA of Winston according to Mark Schlabach of ESPN.com.
"According to the DNA analysis report, a copy of which was viewed by ESPN.com on Wednesday, the Florida state crime lab determined the chance of the DNA in the woman's underwear being a match for someone other than Winston was one in 2.2 trillion."
This report comes a day after the Tampa Bay Times reported that a detective warned the accuser's attorney that "Tallahassee was a big football town and the victim needs to think long and hard before proceeding against him because she will be raked over the coals and her life will be made miserable."
While that looks bad for the police department, the biggest piece of evidence so far against Winston is the DNA test. But there is more to that than just a positive result.
What does the DNA test mean?
First of all, it is impossible to prove that DNA came from a specific person unless we were able to obtain the DNA sample of every person on the planet. Instead, what happens is that a number of DNA markers are tested (~20). The more markers that match, the less likely it is that the DNA sample came from somebody else.
In this case, there were enough matches between Winston's sample and the underwear that there is a "one in 2.2 trillion" chance that somebody else has an identical DNA profile. In other words, it is highly unlikely.
Does a DNA match prove a sexual assault took place?
All a DNA match tells us is that the person was likely in contact with that item of clothing at some point. The presence of DNA does not tell us how the DNA got there.
Something not included in the report by ESPN.com is whether or not the underwear tested positive for semen. This is actually a much simpler test than the DNA test. It is also important as it would suggest that there was sexual contact. But again, that doesn't prove a sexual assault occurred.
Among the many questions that still need to be answered are:
Does the suspect deny that there was any sexual contact? If he does deny there was any sexual contact, he can be painted as a liar since there is strong evidence he was in contact with her underwear and there may be proof of sexual contact.
Was there any previous sexual history between the two? If so, especially in the days prior to the alleged assault, that could be used to explain the presence of DNA and possibly semen on the underwear.
Ultimately, the presence of DNA on the underwear is an important revelation and can be used to show a sexual assault occurred. But there is still much more that needs to be answered before the case can move forward.