Defense challenges ‘catfishing’ theory in Herndon au pair murder case, claims detectives were silenced

This Fairfax County, Virginia, house is the scene of a double killing, in which the husband and the family's au pair have been charged. (WTOP/Luke Lukert)

The aggravated murder trial of a Fairfax County man charged with killing his wife and another man in the couple’s home doesn’t begin until October, but defense attorneys for Brendan Banfield are challenging the “catfishing” theory that led to his indictment.

Fairfax County police and prosecutors have said Brendan was impersonating his wife, Christine Banfield, in an online account on a fetish website. Prosecutors said the husband lured Joseph Ryan to the couple’s Herndon-area home as part of his plot to kill his wife, since Brendan was having an affair with the family’s au pair, Juliana Magalhaes.

According to police and prosecutors’ catfishing theory, Brendan and the au pair killed Christine and Ryan, claiming they had interrupted a home invasion.

During a pretrial hearing Thursday, John Carroll, Brendan’s attorney, told the judge that two detectives who believed digital evidence suggested Christine was the one sending messages to Ryan were pressured and silenced by Fairfax County police supervisors. Both detectives were also transferred off the high-profile case.

Magalhaes was charged nearly a year before Brendan was arrested.

The au pair pleaded guilty in October to a lesser charge — involuntary manslaughter — after providing police with a detailed description of what she said happened. Under the plea agreement, Magalhaes would be deported after testifying against Brendan in his Oct. 20 trial.

According to NBC Washington, Judge Penney Azcarate ordered prosecutors during Thursday’s hearing to provide the defense with internal police communications that led to the transfer of detective Brendan Miller.

Commonwealth’s Attorney Steve Descano said in a statement 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.”

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Neal Augenstein

Neal Augenstein has been a general assignment reporter with WTOP since 1997. He says he looks forward to coming to work every day, even though that means waking up at 3:30 a.m.

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