April 3, 2022

Diane Staudte // 105 // The Antifreeze Murders

Diane Staudte // 105 // The Antifreeze Murders

Diane Staudte and her daughter, Rachel, committed murders together by poisoning their family members with antifreeze.  Diane's husband, Mark was murdered first, then her son, Shaun.  Soon after, her daughter, Sarah was taken to the hospital in critical condition and police started an investigation.  Diane was sentenced to life in prison without the possibility of parole and Rachel was sentenced to life in prison and she will not be eligible for parole for 42 1/2 years.

Website: Drinking The Cool Aid



Diane and Mark Staudte (Stow-dee) met in 1984 at a bluegrass festival and they really hit it off. Mark was fun, lovable, outgoing, and was very involved in his band. He wrote many songs and music was really his passion from a very young age. The couple had four kids and the family of six lived in a 900 square foot home in Springfield, Missouri. So, this was a pretty tight fit. They became members of the Redeemer Lutheran Church and Diane was involved in pretty much anything musical at the church. Diane sang and played the organ and her daughter Rachel also sang. Faith was very important to the family. Diane was a trained nurse and she worked full time in the health insurance industry.

Diane and Mark's first child was named Shaun and he was diagnosed with Autism at age 5. Family members believed that Diane didn't want to admit that he was autistic. Their next child, Sarah, had extreme separation anxiety and she would scream and throw temper tantrums all the time. Mark didn't have a job, so he stayed at home, but he mainly played his music. He wasn't cleaning the house or taking care of the kids. He did play in a blues band and occasionally picked up shifts as a bartender to get some extra cash. Diane had to work her full time job, then come home and take care of everything there. By the time they had Rachel and Brianna, it was a very busy household. Diane claims that her husband began abusing alcohol, but it doesn't seem like other people agree. The Pastor of their church says that he knew the family well and Diane never said anything about her husband drinking. Also, the people from his band say that he would go to gigs in bars and just sing and play the harmonica and he didn't drink because it wasn't his thing. Diane has also claimed that Mark started hanging out with friends and doing drugs, but no one else seems to agree with that statement. 

From the outside, the Staudte family appeared to be pretty picture perfect, but that all changed on Easter of 2012. On the Friday before Easter, Mark met up with his band to do a recording session and that's when they noticed something was off. His skin color was yellow, he was slurring his words, and it was like his brain didn't understand what he was even doing there. On April 7th, a day before Easter, Shaun became concerned about his father and wrote on Facebook: My father is slowly getting sicker. His voice is slurred. His walking is wobbly. Diane was a nurse and says that Mark came home and was stumbling around, so she put him to bed. On Easter Sunday, she wasn't too concerned about the situation, so she got up and went to church. When she got back from church, she saw that 61-year old Mark had stopped breathing. Diane posted on Facebook:

For all my friends on FB, this past Sunday evening, Mark, my husband of 27 years reached his eternal home. 

Mark's band members were completely shocked and said he was performing on stage like he was 21, this just didn't make sense. One of them decided to drive to the house and asked Diane what happened and he said she was so matter of fact, zero emotion when she explained how he died. When he went to the memorial service, he was of course, crying, and mourning the loss of his best friend, but Diane was just blankly staring ahead. People can mourn in different ways, but he felt like this was very odd behavior. Mark's band played his favorite songs at the service and they said Diane was acting like this was just a huge party she was hosting instead of acting like a grieving widow. 

Diane got a $20k payout from Mark's life insurance policy, so she actually moved the family to a new house in Springfield. The Pastor from her church would meet up with Diane for coffee to see how her grief was and if she needed any help. She never asked for prayers or mentioned that she was having a tough time with her husband's death. A few months later, on September 2nd, 2012, there was another death in the Staudte home. The new neighbors obviously noticed the police everywhere and they saw a body being taken from the house, but they were slightly hesitant to go check on things. When the family first moved in, some of the neighbors tried to introduce themselves and when they would approach the house, the doors would shut, so it wasn't a very friendly situation. 26-year-old Shaun had been having severe stomach problems and one weekend, Diane went to church and when she came home, her son was dead. It was noticed that there was an odd blood stain around Shaun's mouth and it looked very similar to the one that his father, Mark had by his mouth. Diane claimed that she didn't take her son to the hospital because he didn't want to go. Even though she was a nurse, she wanted to respect his wishes.

An autopsy was performed on Shaun and it was determined that he died due to prior medical issues related to a history of seizures. He was autistic and had several health issues that came along with that, so it didn't actually come off too suspicious initially.

Diane posted about her son's death on facebook and said the the following:

To my FB friends and family: 

It's been hard for me to come up with the right words, but here goes. On Sunday, my oldest child, Shaun died. Although he had been sick lately, we thought he was getting better. Thank you to those who have called or messaged me, please continue to pray for us during this time.

After Shaun died, the family didn't do anything for him. They didn't have a funeral and there wasn't an obituary. They just had a few people over to the house and then they cremated him, just like she had done with Mark. And when I say they had people over, it was Diane, her Pastor, and one other person. She didn't even have her other kids there.

In the fall of 2012, Diane's daughter, Sarah graduated from college. By June of 2013, when she was 24 years old, she was very ill and had to be rushed to the hospital. She had multi-system organ failure and needed life support. Her organs were shutting down, her brain was shutting down, and she was hemorrhaging. Doctors just couldn't figure out what was causing this and Diane posted on facebook:

Asking for prayers as my daughter Sarah is in critical condition in ICU tonight.

An anonymous call was made to the Springfield police department alerting them that Sarah's current illness was suspiciously similar to what Mark and Shaun experienced before they died. The caller was later identified as the Pastor of the church, Jeff Sippy. He said, “There was nothing in me that believed that it was of a natural cause.” “I didn't believe that he died of a stroke. A heart attack. Or in his sleep. I just didn't. There's nothing scientific. There's nothing professional about my observations. But my first words were no way, he didn't just die.” The police kind of thought, this couldn't be real. They started to look into things and saw that Diane's husband, Mark's death, was from natural causes. When investigators called the officers that were on the scene that day, one of them said Diane had actually stepped over the top of Mark's body and it stuck in his mind because it was so odd. Remember how Mark and Shaun both had blood around their mouth? Well, that's not something that typically happens in a death from natural causes. They needed to figure out what was going on with Sarah to see if they could link everything together.

Doctors were frantically testing Sarah and there weren't any drugs in her system and she didn't have an infection. A nurse informed the doctor that Diane wasn't concerned about the situation and asked that they stop the treatment. Detectives showed up at the hospital and nurses said that Diane was acting really lighthearted about the whole thing. Her daughter is dying and she was joking around with people, talking about going on a vacation and said that Sarah's situation wouldn't stop her from going on a vacation. In fact, Diane was more worried about herself than her daughter at this point. She claimed that she was experiencing back aches, headaches, and she couldn't pee. 

After the detective spoke to Sarah's doctor, they both came to the same conclusion and believed she had been poisoned. The doctor ordered tests for heavy metal poisoning, lithium, and arsenic. Since this is VERY rare, you have to send the tests to a special lab, so it takes longer. At this point, Sarah was on life support to support all of her organs to stay alive. After several days in intensive care, Sarah started to stabilize. 

Detectives were very worried about the other kids in the household, so they brought Diane in for questioning. She said, “I didn't hurt my kids and that's what I feel like you're insinuating I did. I may not be the best mother in the world, but I didn't hurt my kids. When Mark died, it was actually a relief. I just don't tell people that. I don't know what else to say.” 

During the interview, the detective asked if she had a son and she said, “No, not anymore, he died.” “He had a seizure disorder.” and was a “significant burden” to her. Shaun was cremated, but detectives called the medical examiner and found out they still had a tissue sample on file, so they were going to re-examine it. I looked this up and the laws are different in every state, but medical examiners will hold onto blood, and tissue samples for a certain amount of time. For a fee, you can request that samples be held onto for a longer period of time and the example I found said up to 5 years and anyone can request this. So, if a family member or friend dies under very suspicious circumstances, you can just pay them to hold the samples. 

When the detective says they would be testing Shaun's tissue, Diane started to change her story. She said she doesn't really know about her kids, but her husband, Mark, was getting into drugs with his friends, so she wouldn't be surprised if that came up. She said that her son, Shaun had been looking up things on the internet and had been threatening to take his own life. She said Sarah also wanted to harm herself. So, her husband took drugs, and her two kids want to take their own lives, that's where we're at. Then Diane says, ok listen. I knew that they were all drinking antifreeze. I found out about it and I was so mad, I didn't want to take them in for help. First off, no one just drink antifreeze for funzies, and certainly not a whole family. 

Ethylene glycol is not a typical part of normal toxicology screenings and requires specific testing to detect, which is why it was missed during the initial autopsy. 

The detective decided to go at Diane with a religious angle.

He's like, you're a Christian, I'm a Christian, let's just do the right thing here. It ended up working. Detective Neal McAmis says, you knew they were drinking antifreeze because you gave it to them and Diane says, I didn't know what else to do. She said she put it in Coca Cola for her two kids and put it in Gatorade for her husband. When detectives searched the house, they found antifreeze in the garage and there were bottles of Coca Cola sitting right next to it. 

Diane's daughter, 22 year old Rachel was brought to the police station so they can tell her that her mom confessed to the murders. She said she had no idea that her mom was responsible for the deaths and she was super close with her mom, like best friends. Detective McAmis slid a piece of paper over to Rachel that had an interesting journal entry. Straight out of Rachel's journal on June 13th, 2011, it says,

“It's sad when I realized how my father will pass on in the next two months...Shaun, my brother will move on shortly after.” “It will be tough getting used to the changes, but everything will work out.” This journal entry was almost a year before Mark even died. So, they planned this for a long time. 

Rachel says that she had a lot of bad dreams about her family members dying and she talked to her mom about it and that's when her mom said she was thinking about hurting them. Rachel says she told her mom that in the dream the deaths were quick, easy, they'd go to heaven soon, and they could all move on. Rachel says her father was a drain on the family and he had no concept of money. He was always out partying and hanging out with friends. She and her brother Shaun fought often, so that's why she wanted him out, but she says she believes they could have just put him in assisted living, but her mom wanted to kill him instead. The reason they decided to poison her sister, Sarah was because she stayed in her bedroom and didn't get a job right after college. Oh and Rachel says it's because Sarah is annoying. She also admitted that they were going to kill the youngest child, Brianna in the same way because she was a burden and they were going to poison her root beer. Brianna was only 12 years old and she had a learning disability. 

Rachel admitted that she researched various methods of killing with her mother. They looked into things like suffocation, but ultimately settled on antifreeze poisoning because they knew it was nearly impossible to detect. They ordered the old-fashioned antifreeze online since the new formulas have an added ingredient that makes it taste bitter. She said she was fully willing to murder her father, but she felt that it was “unnecessary” to kill her siblings, but that's what her mom wanted, so she went along with it. 

Diane claims she killed her husband because she hated his guts and just couldn't take it anymore. She said her son Shaun had to die because he interfered with everything she did. She was working from home at this point and he was getting in her way, so she kept telling him to leave her alone and go to his room. She couldn't figure out how to change her situation or get her family out of the house, so she snapped. She poisoned her daughter, Sarah, because she had significant college debt that she didn't want to pay for. 

Rachel and Diane were really close and they were similar. Diane was able to essentially groom her daughter to view Mark the way that she did. Diane thought it would be an easier life if it was just the two of them and she waited for Rachel to be ready for that. I think they bonded closer when this diabolical plan formed. 

You're probably wondering about Sarah, the one in the hospital. Like, why she was even brought in for help. Well, her sister Rachel says that she didn't want another one to die in the house because houses are nasty after someone has died in it. Doctors initially didn't think Sarah was going to make it, but she was brought in JUST in time. She survived, but suffered a lot of brain and organ damage. She actually went to assisted living, had a brain bleed, and had to re-learn how to walk and talk. Sarah says she believed her mom was going to kill her before this happened. She read her mother's journal and it talked about the deaths of Mark and Shaun and listed Sarah next. Sarah confronted her mom, Diane about what she saw and her mom assured her that she wasn't going to die and told her to stop reading her journal. 

Sarah says she no longer considers her mom and sister as people. They are just hateful killers to her and she would love to slap both of them and call them the B word. Even though she is angry, she has forgiven them because she says it's the right thing to do. On the 20/20 episode, this was presented to her mom, Diane and they asked how that made her feel. She says that she is sorry for what her daughter went through, but she's sorry for what everyone goes through and she's sorry for what she, herself had to go through. It was all about Diane and she claims that she was maybe even poisoned herself. She has complete amnesia about all the events that took place and doesn't remember the confession. Sarah actually lives in a group home now and when they showed Diane a picture of her daughter, she goes, “Oh, wow. She's gained weight.” 

She also mentioned that her family was being threatened by someone else and she knows who it is, but can't say anything. A mystery person forced her to confess to the murders and her husband, Mark was involved with dangerous people. She found out while she was in jail that Mark had been green lighted, meaning he had been authorized to be killed. 

There is no evidence that Mark did drugs or was hanging out with anyone that did drugs and there is certainly no evidence pointing to another person outside of the family being involved in this. Diane claims that her son, Shaun took his own life and left a note.

Diane and Rachel were both facing the possibility of getting the death penalty. They both plead not guilty originally. Rachel ended taking a deal to plead guilty and testify against her mom so she didn't get the death penalty. Diane plead guilty and took the Alford plea acknowledging that there is enough evidence to convict her, so she also got out of the death penalty, but will never be eligible for parole. Rachel ended up apologizing to her sister Sarah for her role in the poisoning and said she was scared to stand up to her mom. She will not be eligible for parole for 42 ½ years and she would be around 65 years old at that time. 

The last song that Mark wrote and recorded may have been the most haunting thing of all. His band was called Messing With Destiny and the song is Female Judas. Here are a few of the lyrics: 

You're just a female Judas

You wanna see me crucified

You took everything from me baby, you even took away my life

Your kiss of betrayal baby, it done did me in

Well, the way you treat me mamma, it's some kind of cardinal sin