WORCESTER (CBS) – It’s some of the most crucial evidence in the case, DNA allegedly linking Angelo Colon-Ortiz to the murder of Vanessa Marcotte in April of 2016. There was evidence found beneath her fingernails.

But the defense claims its collection was unlawful and wants it thrown out because Ortiz-Colon, who spoke only Spanish, didn’t understand troopers when he was asked to sign a consent form for a DNA sample which Lt. Robert Parr challenged.

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“His first question was whether he had to take the test or provide the sample,” said prosecutor Jeffrey Travers.

Angelo Colon-Ortiz is accused of killing Vanessa Marcotte in Princeton (WBZ-TV)

“Yes, I told him it was voluntary and that he did not have to provide his DNA,” Parr said. Parr had questioned Colon-Ortiz at his Worcester home after spotting him in a dark colored Ford Escape that matched the description of one seen near the murder scene.

At the home Parr brought trooper Thiago Miranda to translate English to Spanish for Colon-Ortiz, but Miranda admitted this to the defense. “I’m able to communicate, I’m able to exchange ideas and information, but I can’t sit here and tell you I’m a professional interpreter,” he said.

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The hearing took place as Vanessa Marcotte’s family looked on. The then 27-year-old woman, visiting her family in Princeton, had gone missing during a jog, her body found hours later.

Vanessa Marcotte. (Facebook photo)

Colon-Ortiz’s DNA sample was one of some 330 samples obtained in the investigation. But what he understood at the time is crucial for the defense. “I can’t say if it was difficulty Trooper Miranda was having, or if Colon-Ortiz was having difficulty but there was obviously some miscommunication between them,” said Lt. Parr under cross examination.

Vanessa Marcotte’s family issued a statement: “Vanessa’s family, friends and everyone involved with the Vanessa T. Marcotte Foundation look forward to justice being served. We miss Vanessa every single day. We think she’d be proud of what we are accomplishing in her honor to make the world a safer place.”

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After the two day hearing a judge will take under advisement the request to have the evidence thrown out.

Beth Germano