The video (at the link below) has a little more detail. Note that DNA evidence is not admissable in all jurisdictions that have BSL.
Dog’s DNA saves its life
Last Update: 9/01/2009 6:21 pm
SALINA, Kansas – What happens when you have a dog but nobody seems to know its breed and that dog resembles a pit bull in a city where pit bulls are illegal? […] “It is just our procedure, if it’s a pit bull or looks just like a pit bull, if noone’s claimed it, then they are euthanized,” said Rose Base, Salina Animal Shelter coordinator.
[…] “Everyone was wrong including me,” Cartwright said. “She wasn’t just lab and pit bull. She wasn’t even a Lab. She was like a Heinz 57.”
[…] “I wonder how many dogs passed away because the owners did not know about DNA,” Cartwright said.[…]
Full article retrieved 9/2/09 from http://www.ksn.com/news/local/story/Dogs-DNA-saves-its-life/cwLXohaiok6FK4UW9STZFQ.cspx