Lawyer: Fairfax commanders silenced detectives in au pair murder case

Washington Post

10-07-2025

The double-murder case against Brendan Banfield involves a theory that he posed as his wife to lure a man to visit her before killing them both with the help of the family's au pair. Banfield's defense attorneys took aim at the impersonation theory in court Thursday, arguing Fairfax police commanders reassigned two detectives who thought some evidence suggested Banfield's wife was the one sending messages to the man who died alongside her.
Prosecutors have said that Brendan Banfield, 40, was pretending to be his wife, Christine, in an online account on a fetish-related website when he invited Joseph Ryan to their Herndon-area house for a mock home invasion and rape fantasy so Banfield could kill them both and claim he was interrupting an intruder attack.
But a summary of the case written by Detective Brendan Miller last year repeatedly describes the online conversations as between Ryan and Christine Banfield, and states that 'There is no indication that Christine lost control of her devices' during the six weeks before the slayings. The records show that Christine Banfield's laptop and phone were used to contact Ryan and that one of Brendan Banfield's phones had no such contact, though his second phone for work could not be opened.
The detectives, who testified Thursday they felt pressured by commanders during the investigation, are still involved in preparing the case for trial this fall, and prosecutors said they were transferred for 'performance management' reasons. But one Fairfax deputy chief acknowledged he had said Miller 'will never work a case in major crimes again' before his transfer and that he disagreed with the detective's conclusions after Miller examined the computers and phones of Brendan Banfield; Christine Banfield, 37; and Ryan, 39.
The prosecution argues that Brendan Banfield, an IRS criminal investigator, left his home's front door unlocked that morning, parked a short distance away, and then waited for an alert from his au pair and lover, Juliana Peres Magalhães, to let him know when Ryan arrived. After Ryan went into the house, Peres Magalhães has told police that she called Banfield, who went into the basement with their 4-year-old daughter, then went upstairs and shot Ryan and fatally stabbed his wife. Banfield has also been charged with child abuse for allegedly bringing the young girl to the scene.
Peres Magalhães pleaded guilty in October after providing a detailed statement to investigators, saying that she had helped the scheme by posing as Christine Banfield in some phone calls to Ryan. She also said she retrieved a gun and fatally shot Ryan after he survived the first shot, prosecutors said. She agreed to a plea deal in which she would be convicted of involuntary manslaughter and be deported to her native Brazil after Brendan Banfield's trial, now set for Oct. 20.
Thursday's hearing before Chief Fairfax Circuit Judge Penney S. Azcarate was ostensibly about the claims by defense attorney John F. Carroll that prosecutors weren't turning over all the evidence in the case. And Carroll argued this included the personnel records of lead homicide detective Kyle Bryant and forensics detective Miller, whom he suspected were forced out of their units because they disagreed with the command staff's view of the case, though the detectives didn't provide specifics of the disagreement.
'This investigation is a theory in search of facts,' Carroll said, a theory 'concocted by non-investigative personnel.'
Carroll pointed to an internal affairs complaint filed in January by nine homicide detectives, including Bryant, alleging a hostile work environment caused by conduct from commanders 'that was unwelcome, pervasive and offensive over an extended amount of time.' The Southern States Police Benevolent Association, a police union, has asked the Fairfax County Office of Human Rights and Equity Programs to launch its own investigation, a letter to the agency shows.
'I believe there's a conflict between command staff and the rank and file,' Carroll said. 'A hostile work environment can show that.' Azcarate instructed prosecutors to look for relevant evidence of a conflict in Miller's case.
Fairfax County Commonwealth's Attorney Steve Descano, who watched the hearing, said in a statement afterward that the judge's order required 'prosecutors to access information that is typically not at issue in a criminal matter. We look forward to presenting this case to a jury of community members.'
Carroll asked Miller on the stand, 'So the debate is whether there is catfishing or not catfishing?' Catfishing is when a person poses as another person online to deceptively form a relationship, as was allegedly the case with Brendan Banfield.
'Yes,' Miller replied.
'Your findings don't support the theory of catfishing?' Carroll asked.
'I would say that's a matter of perception,' Miller said.
An executive summary of Miller's digital forensics analysis outlines how Christine Banfield's phone was used to create a new Gmail account in early January 2023 and that a new photo of her was used when creating a profile on FetLife, a website for those interested in sexual fetishes. Christine Banfield had also messaged the photo to her husband, Miller found.
Miller's report repeatedly attributes all actions on Christine Banfield's phone and computer to her, saying that 'approximately 114 messages were exchanged between Christine and Joe' between late January and mid-February 2023 on the FetLife site. 'Christine initiated the transition to Telegram for communication with Joe on 2/19/2023,' Miller wrote.
The devices in the case and Miller's report were then sent to an evidence analysis team at the University of Alabama for peer review. The team issued its own report that confirmed Miller's findings on the uses of the devices.
Deputy Chief Patrick Brusch was in charge of the Fairfax major crimes bureau in 2024. He said that he had a master's degree in computer forensics, though he never served as a detective, and that he reviewed Miller's findings and concluded 'the data was being incorrectly analyzed. … I would say it was incomplete in the deduction.'
Brusch said he expressed concerns to Miller's supervisor 'regarding his abilities as a forensic examiner. It was specific to this case.' He acknowledged telling the supervisor, 'This guy's never gonna work another case in major crimes while I'm the deputy chief,' and soon Miller was moved to the child-abuse unit.
Bryant said he joined the homicide unit from the child-abuse unit in 2021, and Banfield was his third case as lead detective. He said he didn't ask to be transferred out of the homicide unit.
Bryant said he received guidance, as well as pressure, from the command staff. In addition to meeting with captains and deputy chiefs, he said, he met twice with Police Chief Kevin Davis. He did not say what Davis told him.
'Were you ever asked to adopt a theory that you didn't agree was supported by the investigation?' Carroll asked.
'Yes,' Bryant said, though he said he was never told to testify falsely. He said there were further disagreements after Brendan Banfield was arrested in September 2024. He was moved to the sex crimes unit and then to the digital forensics section in January of this year.
Deputy Commonwealth's Attorney Eric Clingan asked Bryant if all 12 Fairfax homicide detectives had different theories about the case, in which no one was charged for more than seven months and Brendan Banfield wasn't charged until more than 18 months after the slayings. Bryant said yes. But after Peres Magalhães cooperated and laid out a string of events, Bryant said there was only one theory.
Azcarate did not order prosecutors to turn over any documents on Bryant's transfer out of homicide.
Carroll said afterward: 'I believe the digital forensics takes the catfishing thing out. And if it comes out, I think it's devastating to their case.' He said Miller's report shows 'there are certain moments where it's clear, it had to be Christine Banfield' who was conversing with Ryan. He said Peres Magalhães told a false story because she was offered a lenient plea deal.