You can now read 10 articles a month for free. Read as much as you want anywhere and anytime for just 99¢.

Suspect’s ex-girlfriend breaks down during testimony

Kathryn McDonough was Seth Mazzaglia’s girlfriend when she lured 19-year-old Elizabeth ‘‘Lizzi’’ Marriott, of Westborough, Massachusetts, to their apartment.

AP/Portsmouth Herald/Rich Beauchesne/Pool

Kathryn McDonough was Seth Mazzaglia’s girlfriend when she lured 19-year-old Elizabeth ‘‘Lizzi’’ Marriott, of Westborough, Massachusetts, to their apartment.

DOVER, N.H. (AP) — The star witness against a man charged with raping and strangling a University of New Hampshire college student broke down on the stand Tuesday, saying she can’t get the image of the victim’s death out of her mind.

Kathryn McDonough is a former girlfriend of defendant Seth Mazzaglia, who’s charged with first-degree murder in the death of Elizabeth ‘‘Lizzi’’ Marriott on Oct. 9, 2012.

Continue reading below

During her fourth day of cross-examination, McDonough began sobbing as she blurted out that she couldn’t remember minor details from that night because the image of Mazzaglia strangling Marriott, who was 19, takes over her mind.

Defense attorney Joachim Barth immediately challenged the authenticity of her outburst.

‘‘You cry without tears, Ms. McDonough?’’ he said.

Continue reading it below

No tears were visible in her eyes, and she did not reply.

McDonough originally told defense investigators that she and Marriott were engaged in rough sex involving restraints when Marriott died. She said she lied to protect Mazzaglia but changed her story after being given immunity from prosecution. She is serving a 1 1/2-to-3-year sentence after pleading guilty last July to conspiracy, hindering the prosecution and witness tampering. Her plea deal hinges on her testimony against Mazzaglia.

Barth has peppered McDonough with questions in a bid to undermine her credibility. He questioned her about details she omitted from her grand jury testimony last year, including a text message she received from Mazzaglia that she has testified was a coded reference to an imminent sexual advance on Marriott in the Dover apartment the couple shared. She testified she lured Marriott, her friend and co-worker, to the apartment because Mazzaglia wanted women to join their sexual relationship.

Prosecutors say Mazzaglia and McDonough dumped Marriott’s body in a river. Marriott, who was from Westborough, Massachusetts, would have turned 21 on Tuesday. Her body hasn’t been found.

McDonough talked with investigators from Barth’s office two days after Mazzaglia’s arrest on Oct. 13, 2012. She had testified she told them one of the stories she had Mazzaglia had concocted to cover the killing, saying Marriott had a seizure and died during rough sex.

‘‘In our office you didn’t cry, you didn’t flinch,’’ Barth pointed out to her Tuesday.

She answered that it was because she was telling them a lie.

‘‘It wasn’t real,’’ she said. ‘‘I was able to push the images aside and keep up with the fake story I was telling you.’’

Barth pointed out that, when asked during grand jury testimony last year whether she had anything she wanted to tell Marriott’s family, her response had been, ‘‘She got into a bad situation.’’

He contrasted that with her sobbing statement of remorse last week, when she said, ‘‘Because of us she never got to live her life.’’

McDonough testified Tuesday that she has been ‘‘at a loss for words’’ to describe her emotions since Marriott died.

Jurors on Tuesday also heard a recorded jailhouse conversation between Mazzaglia and McDonough less than two weeks after his arrest, in which they discussed plans to marry despite his incarceration.

‘‘I'm sorry it couldn’t have a little more pomp and circumstance to it,’’ says Mazzaglia, who is not expected to testify.

McDonough returns Wednesday for a seventh day of testimony.

More coverage:

Ex-girlfriend of alleged killer in N.H. says ‘I’m not lying’

Witness says she wanted to protect murder defendant

Defense lawyers challenge ex-girlfriend’s story at N.H. trial

Ex-girlfriend describes rape, murder of UNH student

Loading comments...

You have reached the limit of 10 free articles in a month

Stay informed with unlimited access to Boston’s trusted news source.

  • High-quality journalism from the region’s largest newsroom
  • Convenient access across all of your devices
  • Today’s Headlines daily newsletter
  • Subscriber-only access to exclusive offers, events, contests, eBooks, and more
  • Less than 25¢ a week