Britany Barron, the Jaffrey woman accused of hiding Keene resident Jonathan Amerault’s body after, authorities say, her husband killed him last year, plans to plead guilty to charges stemming from Amerault’s death, according to a new court filing.

Documents filed Friday in Coos County Superior Court, where Barron faces three counts of falsifying physical evidence, a felony, indicate that she intends to plead guilty to all three counts as part of a plea deal with state prosecutors.

Under the terms of that deal, which were filed with the court, Barron, 32, would be sentenced to 1½ years in prison and have the 11 months she’s been in jail count toward that term. She has agreed to cooperate with prosecutors on their case against her husband, Armando Barron, including by possibly testifying against him.

Britany Barron, who also faces two counts of abusing a corpse, a misdemeanor, would have those charges dropped under the agreement with prosecutors.

A plea hearing in her case is scheduled for Monday in Grafton County Superior Court in North Haverhill. Her Keene-based attorney, Richard Guerriero, declined Friday to comment on the plea deal until after it’s presented in court.

Barron has been held at the Grafton County jail since late last September, when she and her husband, Armando Barron, 31, were arrested in connection with Amerault’s death earlier that month.

Police have said Armando Barron shot and killed Amerault, 25, overnight between Sept. 19 and 20 after luring him to Annett Wayside Park in Rindge when he discovered that Britany Barron and Amerault were romantically involved. In an affidavit, N.H. State Police Sgt. Stephen Sloper wrote that Britany Barron said her husband tried to make her kill Amerault but that she refused.

A Coos County Superior Court judge denied Britany Barron’s request for bail earlier this year, saying he felt prosecutors had shown that if released, she would be a threat to the community.

In arguing for Britany Barron to remain incarcerated, Assistant Attorney General Scott Chase said that while she and her husband were in separate vehicles after Amerault was shot, she had both a cellphone and a loaded gun, but didn’t take action to stop her husband’s efforts to evade police or report him to authorities herself.

“Every time she was presented with an opportunity, she made an unlawful choice to further Jonathan’s murder, to conceal and destroy evidence and to ensure that a murderer walked free,” Chase said during a hearing.

Britany Barron told police that after her husband killed Amerault, the couple took his body north, driving Amerault’s car and their own vehicle, according to the affidavit. N.H. Fish and Game officers discovered his body two days later in an unincorporated area of Coos County.

Sloper wrote in his affidavit that Britany Barron said she had decapitated Amerault’s body and attempted to hide his remains, on her husband’s orders.

She also told police that Armando Barron severely beat her after discovering that she’d been romantically involved with Amerault, according to the affidavit. Britany Barron’s mugshot shows her with a pair of black eyes, including one with a broken blood vessel, and other photos from the investigation show significant bruising on other parts of her body.

Armando Barron, who faces a slew of charges in Cheshire County Superior Court including capital murder, has denied his wife’s allegations. He is being held at the Cheshire County jail in Keene.

Guerriero, Britany Barron’s attorney, said his client had a strong duress defense, and that victims of domestic violence often act in ways that are different from how they’d normally behave. He asked the judge to consider her actions in the context of what Armando Barron, who also faces multiple counts of assault, is accused of doing to her before Amerault’s murder — pointing to guidance from the N.H. Attorney General’s Office on cases involving domestic violence.

“To the extent that the state faults Ms. Barron for her conduct and for any of her statements, beyond the duress she was under, beyond the threat to her life and everything else, her behavior pretty much exactly matches what the AG describes ... as the stereotypical behavior of a victim of domestic violence,” Guerriero said at the time.

Caleb Symons can be reached at 352-1234, extension 1420, or Follow him on Twitter @CalebSymonsKS.