Crime & Safety

State to Jury: Do Not Let Seth Mazzaglia Get Away with Murder

NH Prosecutor: "Send him the message you've seen through it all and know the truth about him: That he is a cold-blooded killer."

DOVER, N.H. – The state prosecution delivered its closing argument in its case against Seth Mazzaglia on June 25 by asking jurors to deliver justice to "a cold-blooded killer."

Mazzaglia, 31, is on trial for the first-degree murder of Elizabeth "Lizzi" Marriott on Oct. 9, 2012.

Marriott's body has never been found, but prosecuting attorney Geoffrey Ward said investigators found her hairs, recovered her sweatshirt, found her DNA and found his fingerprints in her car. Ward said investigators also recovered numerous text messages and other evidence between Mazzaglia and his ex-girlfriend, Kathryn McDonough, about the duo trying to hide the murder.

Ward said jurors were given a "glimpse into the defendant's own twisted mind," from his fanciful escape plans from jail to his scheme to kill off two people who testified to seeing Marriott's body in Mazzaglia's apartment in Dover, N.H.

"All of his attempts to avoid responsibility for what he did that night have failed thus far," Ward said. "This trial, his misdirection now, pinning it on McDonough, is his last attempt to avoid responsibility for his murder and his rape of Lizzi Marriott."

Ward referenced the lies, cover-ups and manipulations described by witnesses since the trial began and he then looked to the jury box. "Send him the message," Ward said, "you've seen through it all and know the truth about him: That he is a cold-blooded killer."

Mazzaglia's defense team, in its closing arguments Wednesday morning, asked jurors to find their client innocent based on what it called unreliable testimony by McDonough.

McDonough, 20, struck a deal with the state last year and agreed to testify against Mazzaglia, 31. She testified that Mazzaglia strangled and raped Marriott, a 19-year-old University of New Hampshire student from Westborough, Mass., when she refused his advances and their desire to participate in bondage and sadomasochism sex after a game of strip poker.

Defense Attorney Joachim Barth argued McDonough was the one responsible for Marriott's death. He told jurors to consider the number of times McDonough lied and the various accounts she told to investigators, including an early story about how Marriott died during rough, consensual sex.

McDonough, the state's key witness, testified for her own self-interest and to avoid longer time in prison, according to Barth. He referenced testimony that she had "voices in her head" and had a questionable mental state.

"Am I arguing to you that she is fully psychotic?" Barth said. "No, I'm arguing to you that there is something different going on here."

Ward said the case, however, is about Seth Mazzaglia – the role-playing gamer with multiple aliases or personas, such as "Dark Heart" and "Doomsday" – and his homicidal rage that night. He described Mazzaglia as a scheming, controlling older man who was lost in "twisted fantasy" when he strangled and raped Marriott. 

Judge Steven M. Houran will give jury instructions June 26 and the jury will then begin deliberating the case in Strafford County Superior Court in Dover, N.H.

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