That some of the suspects mostly unknown to cops who committed some of the profiled cases is most likely in custody but police don't realize it yet?

Some cases i'm thinking the Lisa Ziegert case the murdered aspiring school teacher who worked at the card shop.

Maybe the guy who kidnapped Angela Hammond,

So many other cases could have the culprit already in prison and not know it.That is why all across the United States , if you are arrested they should have a required DNA sample taken.

Perhaps. I know that Mia Zapata's murderer was already in custody when they linked him to the crime through DNA and bite marks... I loved the fact that even after they had him nailed to the crime through the DNA evidence, he still insisted that he had never met Mia Zapata nor had he ever been in Seattle...