It's possible that this ends in a hung jury, I agree.
The screw-ups in this case raise a lot of reasonable doubt *if* the jurors don't have 100% faith in the DNA evidence (which IMO is pretty solid based on testimony that the sperm was determined to have been left within 30 minutes of the women's deaths- the only way to wiggle out of that is to assert that the DNA evidence was corrupted or the killer was following Bittrolff around: neither of these scenarios is remotely plausible)
"But Suffolk County Assistant District Attorney Robert Biancavilla said that while more than 50 suspects were tested, Mr. Bittrolff was the only one whose DNA matched what was found at both crime scenes. The bodies of both victims were discovered in wooded areas months apart more than 20 years ago. Mr. Biancavilla said a forensics expert testified that both women had sex within a half hour of dying."
https://riverheadnewsreview.timesre...n-accused-of-cold-case-killings-goes-to-jury/
"Mr. Biancavilla said both police officers were eliminated as suspects through DNA. He acknowledged that evidence in both cases were mistakenly destroyed and said it was due to a labeling error."
So I guess that's the answer as to whether DNA for either officer was tested.
What we don't have an answer for (but we all know what it is anyway) is why Officer Murphy was not only allowed to remain on the force but was promoted when he'd been accused by multiple prostitutes of rape.
Sounds like that's just been perks of the job for years now on LI.