FAIRFAX COUNTY, Va. (7News) — Brendan Banfield's lawyer continued bringing witnesses to the stand during his double murder trial on Thursday, as his defense builds a case and looks to poke holes in the arguments the prosecution has laid out so far.

Thursday, however, revealed testimony focusing on the credibility of those investigating the case. One Fairfax County official said they became concerned over a statement made by Banfield's daughter shortly after the murder.

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Banfield, a former federal agent with the Internal Revenue Service (IRS), is accused of killing his wife, Christine Banfield, and another man, Joe Ryan, in an elaborate plot using a fetish website - FetLife - to lure a man and stage a home invasion. 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.

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. That supervisor left law enforcement altogether

Another lead detective was transferred off the case due to a lack of experience, according to multiple supervisors on the stand Thursday.

Defense also pushed witnesses on arguments that supervisors pressured investigators into the sole theory that Brendan and Peres Magalhaes created a catfishing account. One homicide detective told Banfield's defense that she was not pressured to follow up on just theories, and they had an open mind throughout the investigation.

Throughout the trial, Banfield's attorney has insisted digital forensics would prove it was Christine Banfield who created a new Gmail account so she could join FetLife, and that she communicated with Joe Ryan on both FetLife and the Telegram messaging app.

Before Thursday's witness testimony, the defense had called Fairfax County Police Det. Brendan Miller to the stand. He is the digital forensics investigator who was transferred out of the division and off the case.

Banfield's lawyer has argued this turmoil withing the law enforcement agency was because Miller came to a different conclusion, finding these accounts were created - and messages were sent - on Christine Banfield's laptop, and he could not prove she ever lost control of her laptop and phone during their creation or use.

However, during cross examination Wednesday, the prosecution also asked if he could definitively prove Christine Banfield was the actual person using her laptop or phone during activity on these accounts, and Miller said he could not. Additionally, one of the prosecution's witnesses at the beginning of the trial was a crime scene photographer, who testified he found Christine Banfield's phone inside a drawer in a kitchen bar cart, even though she was in the primary bedroom upstairs.

On Thursday, Banfield's lawyer called to the stand the supervisors who requested Miller be transferred out.

Both denied this staffing shakeup was any retribution for not agreeing with what has been dubbed "the catfish theory."

Instead, they said it's because Miller made incorrect and unsubstantiated conclusions based on the digital evidence.

Specifically, both said Miller could not definitively place Christine Banfield with her laptop or phone during 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 Christine would not use these accounts while her husband was out of the home.

Before the court dismissed for the day, 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 she hear 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."

THURSDAY'S TESTIMONY

• Defense calls Fairfax Police officer Casanova to identify the video submitted into evidence.
• Defense calls another officer to the stand for questioning to review video evidence.
• Defense calls Leah Smith, who was part of the homicide detective and investigative unit department on February 24, 2023. Smith testified that early on in the investigation she told a room full of investigators that "no one should have a theory in the case." Smith added: "investigators on this case knew to investigators with an open mind."
• The court takes a morning break.
• The court returned in session and called Matt Nilssen, with Fairfax County Police dept as a Detective sergeant with major crimes bureau to the stand.
• Nilssen testified that early on, Juliana Peres Magalhaes did at one point corporate with investigators.
• John Patrick Brusch, previously with Fairfax County Police, a deputy chief of the administrative support group.
• Brusch testified that he was considering three theories based on the evidence and analysis at the time of the investigation.
• Brush testified that he retired from the police department in 2025.
• Over the course of questions, the defense asked Brush if he was asked to "clean up the homicide division," in which he responded, "no sir."
• Prosecutors begins cross examination. Brush said he "did not collect any evidence in the case."
• John Patrick Brusch is dismissed from the witness stand.
• Defense calls Lt. David Giaccio under the Sully District with the Fairfax County Police Dept.
• Giaccio testified that he was a direct report to John Patrick Brusch while working on the case.
• Defense asked Giaccio to discuss text conversations between him and Brusch.
• The court is in recess for lunch.
• Court resumes at 2:07 p.m. Defense continues questioning with Lt. Giaccio
• Defense calls Saly Fayez in the victim services division. The civil unit falls under the major crimes bureau. Fayez testified that following the death of Christine and Joe Ryan, Fayez suggested getting a hotel room for Brendan Banfield, the Banfield's daughter, Valerie and Peres Magalhaes.
• Fayez was asked to explain the context of text messages between other officers in the police department.
• During cross-examination, Fayez testified that following the death of Christine, an intel detective overheard an exchange between Valerie, the Banfield's daughter and Peres Magalhaes, the au pair that raised the questions and concerns if Christine had been set up.
• On the stand Fayez told prosecutors: "From my understanding we had an intel detective in the lobby of the hotel that we had everybody in and she [Valerie] had asked Juliana [Peres Magalhaes], can I call you mommy now ? ... Juliana, I can't remember her answer, she said yes and then she said are you going to marry my daddy? And Juliana said 'I wish."
• Fayez wraps testimony and is excused from the court.
• Detective Miller returns to the stand for questioning.
• The court is dismissed for the day shortly after 5:30 p.m.

TRIAL RECAP

Banfield's Defense and Witnesses

The defense began Wednesday 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.

However, LeeAnn Singley said she does not agree.

Singley, the defense's blood stain expert, 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.