Ex-Girlfriend of Accused Killer Lied to Cops About Investigation, Prosecutor Says

PHOTO: Kathryn McDonough, 19, of Portsmouth, N.H., is seen in this undated police photo.PlayNew Hampshire State Police/AP Photo
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A New Hampshire woman faces charges of conspiracy and hindering after prosecutors say she lied about her whereabouts and involvement in an investigation into the death of a college student that her then-boyfriend is accused of killing.

Kathryn McDonough, 19, was arraigned Wednesday in Derry, N.H., after she was arrested on Christmas Eve and charged with conspiracy and hindering the apprehension or prosecution of those responsible for the death of 19-year-old Elizabeth "Lizzi" Marriott in October.

McDonough's ex-boyfriend, 30-year-old Seth Mazzaglia, is charged with second-degree murder in Marriott's death and remains in jail.

Marriott, a biology major at the University of New Hampshire, was last seen Oct. 9, after leaving the UNH campus to visit friends six miles away in Dover, N.H. Marriott texted a friend to say she would stop by another friend's home just after 10 p.m., but never arrived. Marriott did not show up at her job at Target the next day, where she worked with McDonough.

Mazzaglia, an actor and martial arts instructor, was arrested and charged with her death on Oct. 13, but Marriott's body has never been recovered despite exhaustive searches of the waters around Portsmouth, N.H, where police believe her body was dumped.

Authorities claim McDonough lied to them during that critical search window.

"On Oct. 12, she gave a statement to investigators investigating Marriott's disappearance, and gave a false alibi as to her and Seth Mazzaglia's whereabouts on the day in question, which was October 9th. And also gave a false alibi as to their interactions with Ms. Marriott that night," Assistant Attorney General Peter Hinckley said Wednesday.

Hinckley said McDonough made "an intentional attempt to disrupt the criminal process."

The court records detailing the murder case against Mazzaglia remain sealed. Prosecutors allege he either strangled or suffocated Marriott in his Dover apartment.

McDonough's attorney successfully argued to have her bail reduced, reminding the court that she is not the one charged with murder.

"These are allegations, not of homicide, but in fact, as I read the complaints, are conspiracy to hinder apprehension," McDonough's attorney, Ryan Russman said.

Judge John Coughlin set bail at $35,000 and set a condition of McDonough's release that she live with her parents in Portsmouth.

McDonough's mother left court Wednesday without her daughter, refusing to comment on the investigation. McDonough's attorney also refused to comment about the allegations that his client is one of the major reasons why Marriott's body is still missing.

"We do not have specifics of the charges. It would be inappropriate to comment," Russman said.