Husband charged in double homicide after having affair with au pair is going on trial in Virginia

FAIRFAX, Va. — A Virginia man who had a relationship with a Brazilian au pair is going to trial Monday in what prosecutors say was an elaborate double-murder scheme to frame another man in the stabbing of his wife.

Brendan Banfield is charged with aggravated murder in the February 2023 killings of Christine Banfield and Joseph Ryan at the Banfields' home in northern Virginia. He has pleaded not guilty in the case.

Banfield and Juliana Peres Magalhães, the family's au pair, were with the wife and Ryan on the morning the victims were killed in the primary bedroom of the Banfield home, court records say. Authorities have said on that day, Banfield and Magalhães told officials they saw Ryan, a stranger, stabbing the wife after he entered the house. Then they each shot the intruder, Banfield and Magalhães said at the time.

Prosecutors have painted a different picture, arguing that Brendan Banfield and Magalhães lured Ryan to the house and staged it to look like he and the au pair shot a predator in defense. Officials have said Banfield and Magalhães had a romantic affair beginning the year before the killings.

Both the au pair and husband were arrested between 2023 and 2024 and initially handed murder charges in the case. In 2024, Magalhães pleaded guilty to a downgraded manslaughter charge after giving a statement to officials confirming parts of their theory.

In that statement, Magalhães said she and Brendan Banfield created an account in his wife's name on a social media platform for people interested in sexual fetishes. There, Ryan connected with the account in Christine Banfield's name, and the users made plans to meet on the morning of Feb. 24, 2023, for a sexual encounter that would involve a knife, authorities said based on the statement from Magalhães.

Prosecutor Eric Clingan said last year that the au pair's statement helped the state solidify its theory ahead of trial.

Not all officials investigating the case have believed Banfield and Magalhães catfished Ryan.

Brendan Miller, a former digital forensic examiner with the Fairfax County Police Department, testified last year that he analyzed dozens of devices and concluded Christine Banfield had connected with Ryan herself through the social networking platform.

An evidence analysis team at the University of Alabama peer-reviewed and affirmed Miller's digital forensic findings, according to evidence submitted to the court.

Miller was transferred out of the department's digital forensics unit in late 2024, though a former Fairfax County commander testified the reassignment was not punitive or disciplinary.

John Carroll, Banfield's attorney, argued that Millers' transfer was directly tethered to the case. He also said in court that Fairfax County police reassigned the case's lead detective after that man had pushed back on the top brass' catfishing theory.