Mary Yoder

Mary Yoder

by Chilling Crimes June 03, 2020 2 Comments

"Hell hath no fury like a woman scorned. Vengeance thy name is Kaitlyn Conley."

-Oneida County Assistant District Attorney, Laurie Lisi

It was the 20th of July 2015. A Monday. Sixty year old Mary Yoder woke around 6.30am that morning at her home in Whitesboro, New York, United States. She had work that day. Mary and her husband William had their own business. They built and ran a successful business, Chiropractic Family Care, for twenty eight years. Mary had more than thirty clients scheduled that day and was due to work a ten hour shift. William was not due to work that day.


Mary Yoder

Mary and William had been married for thirty eight years and had three children, Liana, Tamryn and Adam. Mary loved the Summer time as she loved to have her children and grandchildren over and enjoyed doing the garden. She also had a month long trip planned with William to Europe for later in the Summer. 

It was around 7.45am when Mary left for work and she got there just before 8am. There were already patients waiting for her at the office. The receptionist was also working that day. Kaitlyn Conley had worked with them for a number of years and was now a friend of the family as she had dated their son Adam for a period. She started with them in 2012 as a part time receptionist. Adam worked there briefly too and then Kaitlyn became a full time employee in 2013. 


Chiropractic Family Care

Mary was fine that morning in work and at lunchtime, she went to Utica to visit her ninety three year old mother. She had just moved in with Mary's sister Sally so Mary wanted to see if she had settled in well. Mary returned to the office sometime between 1pm-1.30pm. At 4.30pm, Mary suddenly did not feel well. She had nausea, vomiting, diarrhoea and abdominal pain. It was just after 6.30pm when Mary got home and she spent most of the evening in the bathroom. Her condition did not improve. That night Mary slept in the living room as there was a bathroom beside it.

William woke at 6.30am the next morning. He noted that Mary had not improved and looked pale, drained and exhausted so he rang their daughter Liana. Liana was a Doctor. She told William to bring Mary to the hospital.

At 9.30am, William and Mary arrived at the hospital and various tests were carried out on Mary throughout the day. Nobody knew what was wrong with her but her condition seemed stable.Mary was told she would have to stay overnight in hospital as more tests were needed. William went home. At 5.30am the next morning, July 22nd, there was loud banging at his front door. When he opened the door, two State Troopers told him the hospital were trying to get in touch with him so he rang them. Mary's condition had deteriorated overnight and she was now in an intensive care unit. 


William discovered that during the night, Mary fell in the hospital room and suffered a cardiac arrest. They had no explanation as to why Mary was getting worse. Throughout the day, Mary went into cardiac arrest seven times. At 2.54pm that day, the 22nd of July, Mary died. 

An Autopsy and blood tests were carried out and it took a few months to determine what had caused Mary's death. Mary's tissues and organs had been under severe attack and that is a telltale sign of poison so they tested for that. The Medical Examiner's Office determined that Mary died as a result of colchicine toxicity. Colchicine comes from a plant known as Autumn Crocus and is a highly toxic substance and in pill form, it is commonly used as a treatment for gout.But if a person ingests a lethal dose, death is normally the outcome as the toxin is quickly absorbed into the body. As the toxin continues to be absorbed into the body, the major organs start to shut down one by one. It can also cause repeated cardiac arrest and normally results in death. 

Autumn Crocus

The initial symptoms of colchicine begin to take effect within two to eight hours and can often be between two to four hours after ingestion. Symptoms are nausea, vomiting, diarrhoea and abdominal pain. It basically causes all of your liquids to leave your body. 

Mary Yoder's death was ruled a homicide by the Medical Examiner's Office. Police began an investigation. On the 23rd of November 2015,the Medical Examiner's Office and the Oneida County Sheriff's Department both received an identical anonymous letter. The person who wrote the letters knew that Mary's death was due to colchicine toxicity and claimed that the person responsible for Mary's death was her own son, Adam. Police asked Adam if they could search his car and he agreed. Based on information in the letters, they searched a specific area of his car and found a small bottle labeled colchicine and a receipt for the purchase of it. Police now knew from the receipt where and when it was purchased. 

Adam Yoder

There was a gmail account on the receipt that was used as part of the online transaction. It was Most of the transaction took place via email but the seller also spoke to the buyer on the phone twice and described the buyer as having a "young soft female voice." The purchase was for one gram container of colchicine and was billed and shipped to the Chiropractor Family Care c/o Adam Yoder.

Police interviewed Adam. Due to the letters and bottle found in his car, he was a person of interest. His father William was also a person of interest due to the fact he was Mary's spouse and some were suspicious when he began a relationship with Mary's sister, Kathy Richmond, shortly after her death. 

But police soon discovered that the evidence led them to a different person entirely. Kaitlyn Conley. 

Kaitlin Conley

When police interviewed twenty three year old Kaitlyn, they asked her if she knew how Mary died. She said that she knew it was due to some toxin. She told them she never heard of the word colchicine. Yet, when the package was delivered to the office, Kaitlyn had signed for it. 

The crime lab developed a female DNA profile from under the stamp on one of the envelopes used for one of the anonymous letters. Kaitlyn's DNA was compared to this and also to DNA profiles found on the murder weapon, that is the bottle of colchicine and the cardboard sleeve the bottle was packaged in. Her DNA profile was present on both items.

Police questioned Kaitlyn about the gmail account. She said that she did not know that account and had not accessed it. Google provided police with the IP addresses associated with the gmail account and the providers of the IP addresses confirmed when and where the gmail account was created, accessed and subsequently terminated. The gmail account was created in September 2014 from an IP address associated with the Chiropractor Family Care. It was accessed several times from IP addresses connected to Kaitlyn's phone and her home. 

Kaitlyn Conley

The gmail account was used almost exclusively for the specific purpose of the purchase of the colchicine. 

A W9 tax form that was required for the purchase of the colchicine was typed out using a typewriter at the Chiropractic Family Care on the 14th of January 2015 when Kaitlyn was working there. The colchicine was bought using a gift card. That gift card was bought by Kaitlyn. Her phone contained images of research on poison. The evidence was mounting up against Kaitlyn. 

Police asked her directly if she sent the letters. She admitted she did. 

William Yoder 

Kaitlyn Conley was charged with second degree murder in the death of Mary Yoder.

At the Trial, the defense claimed William was to blame for Mary's death. They believed he likely laced Mary's daily protein shake that morning before work and that is why he decided not to work that day. They believed he had a motive and that was in the form of an alleged illicit affair with Mary's older sister, Kathleen Richmond.

The prosecution disagreed. They claimed that all of the evidence proved it was Kaitlyn. They believed the motive for murder was revenge. After Adam ended their relationship, she wanted him to pay and that is why she poisoned his mother and sent letters trying to frame him for murder. 

Kaitlin Conley

The Jury could not reach a verdict and the Trial ended in a hung jury, a mistrial. Five months later, Kaitlyn was tried again but this time they didn't accuse William, the defense blamed Adam instead. 

At her second trial, the Jury was told they could consider first degree manslaughter. The Jury at one point told the judge they couldn't reach a decision but the judge told them to keep deliberating. They did and the Jury reached a verdict. They found her guilty of the lessor charge of first degree manslaughter.

Mary's family asked the Judge to give Kaitlyn the maximum sentence. They noted that she had expressed no remorse for the violent and painful way she ended Mary's life. Mary's daughter Tamryn said:

"We were told early in the investigation that this murder did not follow to the category of a violent crime. I would like to argue that from what I witnessed, as my mother's body slowly died, was indeed violent. My children had the innocence and wonder of childhood ripped away from them. Evil and violence stole the most magical loving person from their lives. And that is not something that can be recovered or healed."

Kaitlyn was sentenced to twenty three years in prison.  

Chilling Crimes
Chilling Crimes


2 Responses

Joyce Hughes
Joyce Hughes

February 24, 2022

Katie Conley committed premeditated murder, and should have been convicted of first-degree murder. In my opinion, Katie should have received a life sentence without the possibility of parole or the death penalty. She does not deserve any consideration whatsoever for what she did to Mary Yoder and her family.

Susan Schwartz,
Susan Schwartz,

August 29, 2021

It is unfathomable that this psychopath did not get either life in prison or the death penalty. This is an incredible travesty of justice in which the judge and jury are equally abominable in their ruling.
May God give this family the strength to endure and pray she never leaves the walls of that prison.
This ruling is outrageous.

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