Detectives describe tracing double murder as au pair replaced victim

FAIRFAX, Va. (CN) — Months after the murders of Christine Banfield, 37, and a man prosecutors contend was unwittingly lured to the home, the family’s Brazilian au pair, Juliana Peres Magalhães, moved into the master bedroom with Brendan Banfield. But if the two had decided to go on with their lives, police were far from finished with the investigation.

An army of Fairfax County detectives swarmed the residence on Feb. 24, 2023, the day of the murders, and in the months to follow, they continued to sift through evidence. On Thursday, the third day of testimony in the trial of Brendan Banfield, 40, prosecutors called forensic analysts and detectives to help connect the dots of the puzzling double murder.

Throughout the day, witnesses testified before a jury weighing whether Banfield will spend the rest of his life behind bars. Once an IRS investigator, Banfield faces charges of aggravated murder and child abuse stemming from the presence of his then 4-year-old daughter the day of the crime. Banfield contends he is innocent. Magalhães, 25, has pleaded guilty to manslaughter for her part in the case.

One investigator took photos of every room of the house, stopping in the kitchen, where Christine Banfield’s cellphone was tucked away in a drawer. The jury also saw before-and-after photos of the master bedroom. The first photos were of a blood-soaked carpet, blankets and torn pajamas on the floor. Another set of photos was taken months later, after Banfield and Magalhaes had purchased new bedroom furniture and replaced the blood-stained flooring. In the master bedroom closet once used by Christine Banfield, the au pair had moved her clothing.

“Pictures that once featured Brendan and Christine had been taken down and replaced with Brendan and Juliana together,” said Kenner Fortner, a Fairfax officer who took crime scene photographs.

Magalhaes and Banfield had commenced an affair soon after she took the au pair job. She testified that Banfield wanted to end his marriage. Using a fetish website, he posed as his wife and invited Joseph Ryan — a stranger — to the house for a rape fantasy.

Soon after Ryan’s arrival, Banfield confronted him, shooting him in the head. He then stabbed his wife to death, according to Magalhães. When Banfield saw Ryan move, he directed Magalhães to shoot the man again.

Banfield contends that he confronted Ryan, who had entered the house and was in his bedroom, according to his defense attorneys. Ryan stabbed Christine, and Banfield shot Ryan.

Police didn’t arrest Magalhaes until October 2023, eight months after the murder. Banfield was charged nearly one year later.

Prosecutors have charged that Ryan’s body was posed. Police noted the strange position in which they found Ryan. When officers first arrived, Ryan’s hands were folded across his chest, and his pants were oddly situated, according to Terry Leach, a Fairfax detective.

The knife used to kill Christine Banfield was found underneath a blanket. As one of the prosecutors displayed a photo, Leach said, “This is not the original position of the knife.”

He explained that when officers and firemen were attempting to save Christine Banfield’s life, they stepped on the knife. “It [the knife] got kicked and moved around as they were trying to work,” he said.