Smock may have misspoken when he said “this is speculation but if the DNA from our case matched up with this guy, we would go forward no matter what was happening.” But I think his comment means usable DNA was found. JMO.
So, if usable DNA was found but no arrest has been made, what does that mean? Here is something from the Iowa DCI regarding DNA:
Should cases without suspects be submitted?
Yes. "No Suspect" crimes against persons should be submitted for testing. In many cases DNA evidence left at the scene may be the only link to potential perpetrators. The DNA profiles obtained from "No Suspect" cases are placed into a computer database and searched against DNA profiles from convicted offenders as well as evidentiary samples from additional "No Suspect" cases.
snip
CODIS has proven to be an effective tool for providing investigative leads to law enforcement agencies. This is particularly true when no suspect has yet been developed. Upon entry into CODIS a DNA profile may be compared to DNA profiles obtained from Crime Laboratories across the country for potential matches. This exchange of information allows a DNA profile from one crime scene to be linked to a separate crime scene in a different jurisdiction. Additionally, CODIS eligible DNA profiles will also be compared to DNA profiles obtained from individuals convicted of qualifying offenses.
http://www.dps.state.ia.us/DCI/lab/dna/
The National DNA Index (NDIS) contains over 10,581,700 offender profiles, 1,641,400 arrestee profiles and 514,700 forensic profiles as of September 2013.
http://www.fbi.gov/about-us/lab/biometric-analysis/codis/ndis-statistics
So if DNA was found and compared to all of the CODIS entries, and no hit was made, that rules out a heck of a lot of people.
This makes me think our perp might be a first time offender or someone who has not been caught (yet). Someone like Austin Sigg, who killed Jessica Ridgeway in Colorado. JMO.
On the other hand, there is a backlog of DNA samples waiting to be processed across the country, so maybe our perp's sample just hasn't made it to CODIS yet.
I hope this stirs up a few comments!