Roy78
There is a lot of misunderstandings in this thread so far. For one, on the idea that "sperm does not automatically equal murder," is of course logically true. DNA evidence doesn't equate that point, but it does suggest that there is a putative perpetrator who could be responsible for the crime. It's not up to forensic scientists to decide who committed what crimes. We can tell that the person was "there." It's up to the detectives to argue/figure out, and ultimately the judicial system to decide the outcome/verdict.
She was raped and killed, who's DNA was on the vaginal swab? Most likely the perpetrator.
Secondly, to suggest that modern DNA forensic science is questionable is farce. There have been major issues with interpretation in the past with non-accredited crime labs/analysts/methods/persons making bogus conclusions, but these days, and for the last 15+ years, has just plain not happened. If there were unqualified interpretations they would be thrown out of the courthouse in a nanosecond.
The absoluteness of DNA mixture interpretations is getting better and better. Google "probabilistic genotyping." A human can reasonably look at data and discern multiple DNA profiles up to a few people when it comes to certain limited mixtures. Prob. Gen. software can deconvolute up to about 10 distinct people in a DNA mixture. It's basically brute force computing. I bring this up because some of the examples other's posted here happened when such tech didn't exist and bogus interpretations were going on.
As for the ethics point. I have met with many victims personally. Not one has ever not returned genuine overly emotional gratefulness of our efforts. Many brave victims become spokespeople and support for other victims. They tour my lab all the time in wonder. I can't tell you how many cases we've solved. DNA evidence, investigations, then a line up, then "that's the one!" happen all the time. These would have never happened without DNA evidence.
Maybe prior to the early 90's when the technology and chemistries were still kinda crude and not every lab could afford accreditation, but definitely not in the US in the past 10 years.
To be clear I am not arguing about the philosophy of if it's ethical to use DNA databases or facial recognition from driver's license databases. I'm saying comparing the use of DNA evidence to using facial recognition on a driver's license database doesn't make sense.
Disclaimer: I stand neutral in this issue; however, DNA/law is what I currently do for a living.
While it is true on the most basic level that law enforcement do 'collect' and 'store' information about 'who we are,' 'where we come from,' and 'who we will be.' It is only true because crime labs are typically required to store samples long term (mostly because of an idea that in the future, technology in the future will provide better discriminatory power, and for quality control testing/confirmations).
Law enforcement does not process DNA samples in the way that the article suggests, in fact, the vast majority of the time (and legally, this varies state by state), crime labs only use DNA typing technologies that produce information that is limited to "identifying an individual." What this means is in the most elementary way, is that the data generated from DNA samples used in law enforcement today, only contains information equivalent to a fingerprint. DNA samples processed in crime labs (the vast majority of the time) is based on STR technologies and (again, most of the time) it is unlawful for crime labs or law enforcement agencies to use this identifying information any further than the capacity to identify the "who" which is most of the time only searched in a database of convicted offenders, detainees, sex offenders, and/or arrestees.
So no, law enforcement agencies aren't generating/processing information different in capacity to that of a fingerprint.
Is it lawful to collect a fingerprint (or in this case a STR DNA profile) without a warrant or probable cause? I think so, but in their minds searching "forensic unknowns" to a database such as CODIS (you'll have to google this) to generate investigative leads is paramount to finding unconvinced offenders.
Example: Bob is arrested in 2015 for burglary and has a history of misdemeanors the past 10 years. DNA is collected for forensic evidence of this burglary to build a case to convict him of this crime. His DNA profile is searched in CODIS and happens to hit to an unsolved rape case in 1998. His DNA profile matches that found on a vaginal swab of the rape victim. Bob will now be charged with rape in 1998, but who would have otherwise gotten off scott free for the rape if it weren't for CODIS.