FAIRFAX COUNTY, Va. (7News) — The double murder trial of former IRS agent Brendan Banfield, who is accused of killing his wife and another man so he could run off with his au pair lover, focused on technology in the courtroom on Friday, with the accused killer potentially taking the stand before the end of the day as the judge races against the impending winter storm that could cancel trial dates.

The disturbing allegations in this case against Brendan Banfield included that he and his family's live-in au pair planned and executed the murders of Banfield's wife, Christine Banfield, and a stranger, Joe Ryan.

Ryan thought he entered the Banfield's Reston home in 2023 to have consensual sex with Christine. But prosecutors said it was all a setup, ending with Brendan Banfield killing his wife.

Brendan Banfield is expected to testify in his own defense as week two of the au pair murder trial is wrapping up. Banfield's lawyers continue questioning the credibility of the investigation and the detectives involved.

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The court resumed Friday morning, but will likely be impacted due to an upcoming winter weather storm that could impact the DMV.

The defense, on Friday, used their own digital forensic expert, Harry Lidsky, to suggest Christine could have set up that account.

They showed a selfie Christine took back in 2023, trying on a new swimsuit. Later that night, that image was downloaded, and the fetish website was set up.

The question for the jury – who was on her laptop, because around that same time, the suspect’s Gmail account comes into play.

“So, whoever was using the computer at this time at 10:03 and four seconds was clearly aware of the account and had the credentials because this is a successful login," said Lidsky from the stand.

Lidsky continued to testify that, “So, at 10:03:40, we have the photo downloaded to the computer. At 10:04 and 23 seconds under a minute later, that same photo is emailed as an attachment from the alleged suspect's Gmail account to the alleged suspect's Gmail account.”

Lidsky added later in his testimony, saying, “I’m not able to say who was in control of the device for the entirety of this period, but I did see inconsistencies in the usage was not confined just to the accounts related to this investigation. And in this case, that would be the suspect’s alleged Gmail account and the fet-life account so interspersed with that I saw personal account usage with Ms. Banfield’s accounts.”

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Banfield's lawyer spent Thursday asking detectives and supervisors whether there was pressure to reach certain conclusions on a social media fetish account - FetLife - that prosecutors said Banfield and au pair Juliana Peres Magalhaes created.

That account, prosecutors argued, was used to lure a man, Joe Ryan, to the house by catfishing him into believing they were Banfield's wife, Christine. Both were found dead in Banfield's house in 2023.

Banfield's attorney questioned former and present Fairfax County Police homicide detectives and supervisors Thursday about alleged strife and disagreements among investigators relating to what has been dubbed "the catfish theory."

The defense has argued the lead digital forensics investigator on the case was transferred out of the division and off the case out of retribution, because he concluded the FetLife, Gmail, and Telegram accounts used to contact Joe Ryan were created and used on Christine Banfield's laptop, and he did not believe she lost control of her electronic devices during activity on these accounts.

His supervisors, who requested this detective's transfer and who took the stand Thursday, insisted that the staffing shakeup was due to performance issues.

The two police supervisors who testified said they believed the detective made wrong and unsubstantiated conclusions based on the digital evidence. Specifically, they both said the detective could not definitively place Christine Banfield with her laptop or phone during the activity on the Gmail, FetLife, or Telegram accounts.

One of those supervisors went as far as saying they checked Christine Banfield's digital footprint dating back to the mid-2000s, and could not even find her using porn websites.

That police leader also said there were two occasions when Brendan Banfield and Juliana Peres Magalhaes went out of town for 36-to-48 hours, and there was no activity on the Gmail, FetLife, or Telegram accounts during that time. He noted he found it odd that Christine would not use these accounts while her husband was out of the home.

A digital forensic investigator for the police concluded that Christine likely set up the account, according to defense attorneys on Friday.

The digital forensic investigator's superiors strongly disagreed and removed him from the case.

The defense spent hours utilizing their own expert pouring over digital data from Christine's electronic devices to poke holes in the prosecutor's theory that Brendan created the account.

Brendan Banfield and Christine Banfield's parents were in court on Friday, sitting on opposite sides of the courtroom.

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According to investigators, Brendan Banfield was having an affair with Juliana Peres Magalhaes, the family's au pair, when he allegedly planned this scheme so the two could run off together.

Magalhaes testified against Banfield early on in the trial as part of a plea agreement with Fairfax County, claiming that Banfield convinced her to take part in the killings and instructed her on how to move on the days before and the day of the murder.

But the Defense early on had argued that Magalhaes is not genuine with her statements and questioned her memory on some topics and her intentions on taking a plea deal. Magalhaes also admitted to considering a contract from Netflix for the rights to her story.

Before the court dismissed on Thursday, the defense called up Saly Fayez with the Fairfax County Police Department's Victim Services Division. Fayez told the court that she suggested getting a hotel room for Banfield, Peres Magalhaes, and Banfield's daughter, Valerie.

During cross-examination, Fayez told the court an intel official heard Valarie ask Peres Magalhaes, "Can I call you mommy now?" Then Valerie asked if the two would get married, to which Peres Magalhaes said, "I wish."

TRIAL RECAP

Banfield's Defense and Witnesses

Thursday, Banfield's attorney questioned former and present Fairfax County police homicide detectives and supervisors about alleged strife and disagreements among investigators relating to key aspects of the case.

A supervisor insisted that the digital forensics investigator in this case be removed for performance issues. He concluded the fetish account was set up by Christine and not Brendan or Juliana, before being removed was removed. That supervisor left law enforcement altogether

A lead detective was transferred off the case due to a lack of experience.

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Defense also pushed witnesses on arguments that supervisors pressured investigators into the sole theory that Brendan and Peres Magalhaes created a catfishing account. The detective told Banfield's defense that she was not pressured to follow up on just theories.

On Wednesday, the defense began by calling Fairfax County Police officers who were among the first to respond to the initial call.

During their testimony, Banfield's lawyer played an extended version of their body camera footage showing the moments immediately after the alleged double murder.

The majority of the video focused on the officer who accompanied Brendan Banfield from the home to the hospital, revealing his emotional state while awaiting to hear an update on Christine Banfield, and later, after he learned she died from her injuries.

Banfield's lawyer had emphasized his client's emotional response at multiple points of the trial so far.

Even though the video was not played on the screens in the public seating area, family members of both Brendan and Christine Banfield could be seen wiping away tears. During the live stream of the trial, cameras captured Brendan Banfield wiping his eyes during this part of the testimony.

The next expert witness focused on the blood stains at the crime scene.

Prosecutors argued that Brendan Banfield intentionally placed Christine Banfield's blood onto Joe Ryan's body to make it look like Ryan had killed Mrs. Banfield. Peres Magalhaes, the au pair, also testified this was part of the plan.

During her testimony on Tuesday, the prosecution's blood stain expert said the patterns on Ryan's hands and clothes appear to have been the result of someone dropping it there, and not naturally coming out of a wound. That testimony appeared to support what Peres Magalhaes said on the stand.

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However, Defense's blood stain expert LeeAnn Singley said she does not agree.

Singley specifically pointed to the blood pattern on Ryan's forearm. She said she could not make any classification on how Christine Banfield's blood got there, in part because of the hair on the skin.

When the prosecution had their turn to question her, however, she also said that does not necessarily mean she can definitively rule out the possibility of the blood being intentionally placed on the forearm.

Banfield's lawyer has also insisted Christine Banfield was, in fact, the person who actually used this account and communicated with Joe Ryan.

The defense's digital forensics experts share this theory.

Fairfax County Police Det. Brendan Miller said he could not prove Christine Banfield was not in possession of her laptop during activity on FetLife.

However, the defense was unable to get too many other details from the two digital forensics experts they called to the stand.

The prosecution was able to successfully object to many of the defense's questions, with the judge ruling that those questions would be hearsay or speculation. Additionally, Det. Miller also said on the stand that he could not definitively prove Christine Banfield was actually using her computer when there was activity on the FetLife account.