Au pair who had affair with Brendan Banfield describes alleged scheme to kill his wife and another man
By Lauren del Valle, CNN
(CNN) — The au pair who was having an affair with Brendan Banfield when he allegedly killed his wife and another man in February 2023 told jurors Monday about the killings – and the elaborate scheme she said she helped execute.
Prosecutors have alleged that plot was hatched with the au pair, Juliana Peres Magalhães, who was initially charged with murder in the case in October 2023. She has since pleaded guilty to a lesser count of involuntary manslaughter for fatally shooting Joseph Ryan, one of the victims.
The au pair agreed to cooperate with prosecutors against Banfield in exchange for a recommendation that she be sentenced to time served, according to the plea agreement.
Peres Magalhães described Monday – the first day of the double-murder trial – how the killings of Christine Banfield and Ryan unfolded after months of preparation that she said involved luring Ryan to the scene so he could be framed for Christine’s death.
The Virginia family’s Brazilian au pair said she saw Banfield stab his wife repeatedly – and described how she shot Ryan with a gun Banfield taught her to use.
“When I first saw that happening, I ran to the other side of the bed, and I was just crouching down … and covering my ears and covering my eyes,” Peres Magalhães said. “And a few times I looked and I was able to see him stabbing her.”
Banfield has pleaded not guilty to charges of aggravated murder, as well as using a firearm during the commission of a felony. He faces up to life in prison if convicted on the murder charges.
Peres Magalhães first started living with the Banfields in October 2021, and an extra-marital affair with Brendan Banfield began in August 2022, she said. Banfield hatched his plan to kill of his wife not long after the affair began, Peres Magalhães testified.
According to the au pair, Banfield thought his wife was a terrible mother and wanted to be with her instead. Banfield didn’t want to pay for a divorce or share custody on his young daughter, Peres Magalhães said.
Using his wife’s laptop while she was home, Peres Magalhães and Banfield created a fake email address and an account on a fetish website, where Banfield planned to find a man they could eventually frame for his wife’s murder, the au pair testified.
They were seeking someone who would carry out a rape fantasy, and the jury saw messages from the fetish website where Peres Magalhães said she and Banfield vetted possible candidates to fill the specific role. They eventually found Ryan, with whom Banfield spent a month cultivating a relationship.
“He made Brendan feel confident enough that he would be the person to play the role that he needed a person to play, which means being aggressive and hold her down and come over to the house and bring stuff,” Peres Magalhães testified.
During opening statements earlier in the day, Banfield’s defense attorney said investigators initially concluded Christine Banfield had control over her devices and accused law enforcement of manipulating evidence to pin the blame on his client.
And Peres Magalhães was arrested in October 2023 to pit her against Banfield, defense attorney John Carroll told the jury.
“The whole reason she was arrested was to flip her against my client,” Carroll said.
In her opening statement Tuesday morning, prosecutor Jenna Sands told the jury Ryan had been lured to the Banfields’ home for what he thought was a consensual sexual encounter with Christine Banfield.
“Those two individuals had no reason to know each other but for the plotting and planning of Brendan Banfield,” Sands said.
Jurors hear 911 calls
The case began February 24, 2023. Calls to 911 led police to the Banfields’ Herndon, Virginia, home, where they found Christine Banfield, 37, dead of stab wounds, and Ryan, 39, dead of gunshot wounds nearby.
Tuesday morning jurors heard the 911 calls made from the Banfields’ home.
One 911 recording made at 7:47 a.m. was disconnected after a dispatcher answered the call. A dispatcher then called the number back and left a message when no one picked up.
Prosecutors have said Peres Magalhães called 911 at that point, but at Banfield’s direction, hung up before saying anything.
At 8:02 a.m. Peres Magalhães called 911 again and spoke to a dispatcher, stuttering but eventually telling them “her friend” had been stabbed.
“I need help …. my friend, she’s been stabbed with a knife and now she’s bleeding a lot. I don’t know what to do anymore,” Peres Magalhães could be heard saying.
After attempting to relay the home address to the dispatcher but stuttering and gasping for breath, Banfield took the phone from Peres Magalhães.
He gave his name and identified himself as a federal agent.
Banfield then said, stuttering at times on the recording, “There’s somebody here, I shot him. But he stabbed her. She’s bleeding. She’s got several marks on her neck. What do I do?”
Before the killings, Banfield, posing as his wife, gave Ryan strict instructions.
“The door will be unlocked. Christine will be asleep in bed. Come straight upstairs. Cut off the clothing. Tie her. Rape her. Simple and fun. That was how it was posed,” Sands said in court. “They would not meet in person beforehand. Joe’s phones would be left in a car. Joe was to bring a knife, zip ties, chains and, most importantly, he was not to stop even if she looked terrible, even if she was calling for help. He was to follow through, because that’s what she really wanted.”
Defense refutes ‘catfish’ theory
During opening statements, Banfield’s defense attorney accused law enforcement of manipulating evidence to fit the theory that Banfield “catfished” Ryan posing as his wife.
Initial digital forensics analysis conducted by investigators, however, found that Christine Banfield had control over her devices before her death, Carroll said Tuesday morning, and detectives who didn’t support the catfishing theory were removed from the case.
“In the world of digital forensics, there’s a saying, digital forensics doesn’t lie, people lie. And there’s going to be plenty to see. You’re going to see manipulation within the police department,” Carroll said.
Brendan Banfield and Peres Magalhães put his daughter in the basement and then went upstairs to the Banfields’ bedroom, with Brendan Banfield holding his service weapon and the au pair holding a firearm he had purchased a month earlier, according to prosecutors.
Banfield was an IRS investigator at the time, Magalhaes said.
Banfield shot Ryan then stabbed his wife, according to prosecutors. Peres Magalhães then shot Ryan a second time at Banfield’s direction, Sands told the jury
Banfield spent the next several minutes manipulating the crime scene to make it appear like Ryan was an intruder, Sands said. The au pair then called 911 again and they reported the killings as if Ryan was an intruder who had stabbed Banfield’s wife, according to prosecutors.
In the commonwealth’s opening statement, Sands told jurors they won’t have to rely on testimony from Peres Magalhães because convincing “blood evidence” will be enough to convict Banfield.
“While Juliana presents us with the narrative, that story that we wouldn’t necessarily know but for her details, it is the blood evidence that you can rely upon without a doubt,” Sands said.
“The blood cannot lie, and the blood puts Brendan Banfield, standing over Christine, stabbing her in the neck until she died.”
As part of their plan, when Ryan came to the home, Peres Magalhães called Banfield to report that a strange man was at the house, and Banfield was waiting at a nearby McDonald’s so he could return to the home quickly, prosecutors have said.
Banfield was also indicted on a count of felony child abuse and neglect and felony child cruelty related to the killings in December 2024. His daughter, who was 4 at the time, was present at the scene, according to prosecutors.
This story has been updated with additional information.
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CNN’s Eric Levenson contributed to this report.
