Investigation Discovery is examing the nefarious activities of Gregory Agnew, who was found guilty of the 2018 murder of his wife, Martha Agnew, in Ypsilanti, Michigan, but is also suspected of killing his girlfriend, Tammy Niver, 25 years beforehand.
In August 1993, mother of two children, 24-year-old Tammy Niver, disappeared without a trace. The investigators recovered her car but could find no sign of Tammy.
The officers were suspicious of her boyfriend, Gregory Agnew, but didn’t have the evidence to proceed with a conviction, and the case grew cold.
However, 25 years later, Agnew came onto the authorities’ radar when his wife, Martha Agnew, was killed.
On February 17, 2018, Martha was found by her daughter strangled to death in her shared home. She had also suffered a blow to the head, and the police said the killer had attempted to stage the scene like a drug overdose by injecting her with heroin.
Did Gregory Agnew kill Martha to keep her quiet about Tammy?
The 49-year-old had been going through a divorce with her husband, Gregory Agnew, when she was murdered. The investigators concluded that Agnew had killed Martha in the hope of retaining marital assets. And they also now believe he wished to silence Martha, who knew he had killed Tammy.
The police concluded that Agnew had entered Martha’s home while she slept and attempted to inject her with the drugs. Martha woke up at some point, which led to Agnew bashing her on the head and strangling her.
He later returned to the scene while wearing blue overalls to clean up the area and stage the scene. The police later found the overalls, which had Martha’s blood on them.
Agnew was arrested and charged with her murder, and the investigation into his possible role in the death of Tammy Niver was reopened. In September 2019, Agnew was found guilty of murdering Martha and was given an automatic life sentence without the possibility of parole.
The case of Tammy Niver’s disappearance remains an active investigation. Tammy and Agnew’s daughter, Nicole Niver, has spoken about her pain at her father’s refusal to reveal the location of her mother’s remains. She said: “It’s extremely selfish and evil for a man to allow his own blood to suffer this long.”
Agnew currently has an appeal in the system.
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Murder in Ypsilanti: Keith Morrison Investigates airs at 9/8c on Investigation Discovery.