Ample bloody DNA evidence used in a second murder trial leads to a conviction. The only problem (which didn’t seem to bother the jury) is that the man used to live in the house with the victims. Maybe some day markers for “ageing” DNA will be developed. Until then its a battle of circumstantial evidence (a check ledger dated one week before the killings) pointing to the perp weighed against defense claims that found DNA is of little consequence in this type of scenario.

“The only forensic evidence Garcia [the first trial’s prosecutor] had linking Bednarz [defendant] to the bloody crime scene was the bloody [paper] tissue, and defense attorneys were able to call it into question. The tissue found on the floor inside 154 Naomi Drive had a crusty substance, probably mucus, with Bednarz’s DNA in it. The blood of victim Michael Ramsey, had been spattered onto the tissue when Ramsey, 53, and the other victims, Beverly Therrien, 74, and Pamela Johns, 60, were beaten to death, Garcia argued.”

http://www.courant.com/news/connecticut/hc-bednarz-guilty-evidence-20160201-story.html