Lawyers make final case in Fairfax double murder trial connected to au pair affair

Closing arguments are expected to begin Friday morning in a Fairfax County murder trial prosecutors say involved catfishing, a fetish website and an affair with a Brazilian au pair.
WATCH LIVE: Closing arguments expected Friday in ‘au pair affair’ murders trial
Closing arguments have begun Friday morning in a Fairfax County murder trial prosecutors say involved catfishing, a fetish website and an affair with a Brazilian au pair.
Brendan Banfield testified this week in Fairfax County court that he did not devise a plan with the family’s au pair to kill his wife, Christine Banfield, and another man, as prosecutors allege.
“I think that it’s an absurd line of questioning for something that is not serious, that a plan was made to get rid of my wife,” he testified. “That is absolutely crazy.”
Banfield is charged with aggravated murder in the killings of his wife and Joseph Ryan.
He has pleaded not guilty and faces life in prison if convicted.
Lead prosecutor Jenna Sands gave her closing arguments at 10 a.m., highlighting what evidence she said supports the commonwealth’s case, including blood patterns and comments made during Banfield’s testimony.
In his closing arguments, defense attorney John Carroll has tried to cast doubt on the prosecution’s case by citing a lack of testing of DNA evidence found at the scene and accusing investigators of a rush to judgement in the murders.
Carroll also referenced digital evidence that he claims discounts a catfishing theory proposed by detectives.
Prosecutors have said that Banfield and the au pair, Juliana Peres Magalhães, lured Ryan to the family’s home in February 2023 by messaging him from an account they created on an adult fetish website impersonating his wife.
Investigators said the pair fatally shot Ryan and Banfield stabbed his wife, then set up the scene to make it appear as if Ryan had attacked Christine.
Magalhães has backed up prosecutors’ theory, testifying in court about Banfield’s plot to kill his wife.
“I just couldn’t keep it to myself, the feeling of shame and guilt and sadness,” she said in court earlier this month.
Magalhães was arrested eight months after the killings and charged with second-degree murder in Ryan’s death. But she has since pleaded guilty to a reduced manslaughter charge as part of a plea deal.
What Banfield says happened
In his testimony Thursday, Banfield recounted what he said happened on the day of the killings, which occurred while the couple’s 4-year-old daughter was at home.
Banfield testified he came home after getting a call from Magalhães saying a strange man was in the family’s home.
After arriving, he said he heard what he thought were sounds of sex.
When Banfield opened the bedroom door, he said he saw Ryan holding a knife to his wife, who was naked on the floor. Ryan, he said, was clothed.
Banfield testified that he told Ryan to drop the knife, and Ryan replied by telling him to drop his gun.
“I did not want to shoot him. I wanted him to let her go,” Banfield said.
Banfield said he fired his gun after seeing Ryan do a “downward stabbing stroke.”
He said he noticed blood in his wife’s hair but didn’t initially see she had stab wounds.
“Christine told me that she was bleeding out and that she was sorry and that she loved me,” Banfield said.
Banfield said he then heard a gunshot and saw Magalhães holding a firearm.
“I looked up and I saw that Juliana had my other firearm, and I was stunned that Juliana had shot,” he testified.
Prosecutors have questioned whether Christine could have held a conversation with seven neck wounds, which were found in the autopsy.
Prosecutors have argued Banfield stabbed his wife multiple times before Magalhães called 911.
Banfield said he waited to shoot at Ryan out of fear of wounding his wife.
The defense has tried to challenge the catfishing theory by providing digital evidence related to Christine’s phone and laptop use. A digital forensic examiner testified that Christine used both devices at the same time — raising questions about how Banfield could have used his wife’s laptop to message Ryan.
The forensic examiner said he agreed with one detective — who was later removed from the case — that Christine Banfield never lost control of her phone or laptop.
In his testimony, Banfield admitted having an affair with Magalhães. He said both he and his wife had affairs throughout their near 20-year relationship but did not intend to end their marriage.
“We were together the entire time. We didn’t break up at any point,” Banfield said.
Banfield told the court he met Christine when they were freshmen students at Quinnipiac University in Hamden, Connecticut.
Magalhães will be sentenced after Banfield’s trial concludes. She could be sentenced to the time she has already served.
WTOP’s Neal Augenstein and The Associated Press contributed to this report.
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