DNA from multiple individuals was found found on a glove, a sweatshirt, and a rifle. Steward's DNA, Vasata's DNA, and DNA from a third unidentifiable contributor.
"And if there is an indication that there's an unknown contributor, someone will always point to that as the true criminal, the defense attorney is always going to point at that as the real perpetrator," said Tiffany Roy.
Roy is a DNA expert, formally a chemist for Massachusetts State Police. She is often called to testify, and she teaches courses in forensic science.
She says even though the unidentifiable DNA exists in small amounts on the physical evidence, it is very problematic for prosecutors.
"Mixed evidence like this is very difficult to interpret," Roy said.
We asked Jupiter's Chief why says this case is now closed. Here's his answer:
"Based on the number of distinct profiles in this case, and based on the evidence, that we have, we are confident that we have made the appropriate number of arrests."
But police documents show, Charlie Vorpagel's initial statements to police indicated he thought there were three to four masked gunmen.
Today, we asked police for further comment about the unidentifiable contributor. They say this is now in the hands of the state attorney.
"[The unidentified DNA] doesn't tell me a whole lot, there could be more people involved, there might not be, there's no way to know that from the scientific evidence based on some of the variables," Roy said.