Although DNA evidence can seem very convincing, forensic examiners make mistakes. They can run the test incorrectly. They can miss cross-contamination by other DNA. They can misstate the scientific certainty of their findings.
Recently, a New Mexico newspaper and the Associated Press covered what sounded like a light-hearted story. Apparently, someone attempted an armed robbery a Pizza Hut store in Las Cruces.
We've discussed on this blog how genealogy databases like GEDmatch warehouse the DNA results of huge numbers of people who have taken part in genetic testing for genealogy purposes.
If you take a genealogy test, you could be exposing your family, from your kids to your distant relatives, to the possibility of having their genetics exposed to third parties, including law enforcement.
Do people have any real privacy rights when it comes to their DNA? Who should have the right to own or control information about your DNA?
Could ordinary contact with other people spread your DNA to objects you've never touched?
"Rapid DNA" machines are a new phenomenon in criminal justice. Able to process a DNA sample in just 90 minutes, they're often called "the magic box." The machines are small enough to be used by police departments. Until now, DNA testing has been performed exclusively by forensic scientists in neutral, accredited labs.
In an apparent bid to avoid missing a six-year statute of limitations, the Wisconsin Department of Justice recently filed felony charges against a man who mailed a threatening letter to a judge in 2012. Prosecutors apparently obtained DNA from the back of the stamp, which the suspect had presumably licked.
The basic science behind DNA testing is sound enough. Each individual has DNA that varies as much as one person varies from another. With the right technology, we should be able to compare a DNA sample found at a crime scene with one taken from a suspect.
Recently, investigators in California arrested a suspect in the "Golden State Killer" case. Joseph James DeAngelo, a former police officer, is accused of murdering as many as 13 people and raping 50 women during the 1970s and 1980s.