Secret Affair Led To Brutal Murder Of Delaware Woman Found With Neck Cut

A Delaware woman was found brutally slain in her home, and an investigation revealed a secret affair directly led to her death.

On Feb. 2, 2005, John Anderson returned from a trip to California and found his wife Mary Anderson’s body lying behind the front door of their New Castle Home. Her throat was slashed and she had suffered multiple stab wounds.

“She had been brutally, brutally murdered,” New Castle County Deputy Attorney General Andrew Vella recalled of the grisly crime.

Mary and John’s bedroom had been ransacked, her purse was empty and her wedding rings were missing. Detectives initially believed Mary could have died during a home invasion or burglary gone bad.

At the crime scene, investigators also discovered bloody footprints inside the home and tracks in the snow outside from a size 11 boot.

The gruesome homicide shocked the community since the 61-year-old grandmother was active in her local church and didn’t appear to have any enemies. But the brutality of the murder led detectives to believe the attack must have been personal.

Mary’s husband of 13 years, John, 62, quickly became a person of interest in the case. He told police that before he discovered Mary’s body, he called her about 20 times and was concerned because she wasn’t picking up.

During the course of the investigation, detectives learned Jing Weidow, a 29-year-old friend of the couple from church, was possibly the last person to see Mary alive since she had dinner with her the night of the slaying.

During a police interview, Jing said after she left the Anderson’s home following dinner, Mary called her and while they were speaking Mary indicated there was possibly someone outside and she was going to check.

One detective on the case who interviewed Jing noted she was “very passionate” about Mary’s husband, John, and appeared “very very much infatuated with this man.”

College math professor John finally admitted to police that he and Jing, a married former student who had joined his church and befriended his wife, were involved in an affair they had carried on for over eight months.

“Mary allowed [Jing] to spend a lot of time with her and her husband,” New Castle County Lt. Teresa Williams said. “They played board games together, they had dinner together.”

Jing even began to call John and Mary “mom” and “dad.” But as time went on, Jing wanted more from John — and he was willing to return her attention. The relationship escalated and they snuck around behind Mary’s back.

In the fall of 2004, Mary complained to her husband that he was spending too much time with their new family friend who was half his age. “Mary Anderson was an intelligent woman, and also an intuitive woman,” Lt. Williams noted. “As most women know, you kind of get a sense when there’s something that’s not right in your relationship.”

Two days after Mary was found dead, police spoke with Jing’s husband, Victor, a 33-year-old auto mechanic. They noticed Victor had a size 11 foot, which matched the prints found at the crime scene.

Victor, however, claimed he was home working on his computer around the time of the murder, and investigators were able to forensically determine he was telling the truth.

Jing quickly became the focus of the investigation, especially after she failed a polygraph test. She then refused to cooperate with the investigation unless she could first speak with John. When John was brought in to talk with her, he “was telling her that he needed to know what happened to Mary to heal his heart,” Deputy DA Vella said. “He became very emotional with Jing.”

Jing finally broke and divulged what occurred the night Mary died. According to police, Jing said she went to the Anderson residence to confront her lover’s wife and reveal their affair. The two then got into a heated argument. “Mary talked to her about staying away from John,” Lt. Williams said. “Jing saw it as any chance she had at happiness with John was over.”

The dispute escalated, and Jing grabbed a knife and attacked Mary, cutting her carotid artery from behind as Mary tried to run away. Jing staged the crime scene by dragging Mary’s body into the foyer and removing the victim’s clothing. She then went home and got a pair of her husband’s work boots and returned to the Andersons’ house, where she put the boots on, stepped in Mary’s blood and then left tracks throughout the home and outside.

Police said John was horrified at what his mistress had done.

On June 2, 2006, Jing pleaded guilty to second-degree murder and she received a sentence of 30 years behind bars without the possibility of parole.

“Ultimately this person who [Mary] thought was her friend murdered her,” Lt. Williams said.

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