A former teacher from Missouri has been sentenced to 12 years in prison for trying to buy a deadly chemical weapon on the dark web as part of a plot to kill a woman who had broken up with him.
Jason Siesser, 46, of Columbia, was handed his punishment on Tuesday in Jefferson City’s federal court, prosecutors said in a news release.
In August, Siesser pleaded guilty to one count of attempting to acquire a chemical weapon and one count of aggravated identity theft.
Former Missouri teacher Jason Siesser, 48, was sentenced to 12 years in prison after pleading guilty to attempting to acquire a chemical weapon and aggravated identity theft
Investigators said Siesser tried twice in 2018 to buy chemical dimethylmercury, capable of killing hundreds, using Bitcoin on the dark web.
Siesser told the seller: ‘I plan to use it soon after I receive it.’
He is accused of placing the order in the name of a juvenile in his care without permission, but authorities said he was the person who accepted the package he thought contained the chemical when it was delivered.
Authorities said the amount Siesser sought would have been enough to kill as many as 300 people.
Law enforcement officers carried out a search warrant after delivery of the package, which contained a harmless, inert substance.
Investigators found the package on a top of a shelf in Siesser’s garage, as well as earlier delivered packages containing the toxin cadmium arsenide, a toxic compound, which can be deadly if ingested or inhaled; cadmium metal and hydrochloric acid.
Siesser lived and worked at this group home for youths in Columbia, Missouri, and used the identity of a juvenile to order the deadly chemical
A search of Siesser’s home had turned up writings that prosecutors said articulated his heartache, anger, and resentment over a breakup, and a desire for the person who caused the heartache to die.
‘They say I should let it go but my hatred’s just too strong,’ Siesser wrote, according to an affidavit. ‘Letting go of anger is the right thing but it makes me feel so strong I dream about your ending You burn up in flames You suffocate on your own blood Your soul completely drained.’
In another note he wrote in part: ‘Our early ending was all wrong. You discarded me like trash but look how I got strong… The darkness that consumes me will overflow one day. You were there to teach me something I already knew Now it’s my turn to teach you a lesson filled with pain Your life is forfeit, flushed down the drain.’
According to the charging documents, Siesser had two relationships with women that left him brokenhearted.
Siesser was married to a woman and lived with her in the Netherlands until 2012. After years of separation, Siesser and his wife divorced in 2017 when he met another woman in Columbia, Missouri.
When federal agents raided Siesser’s home, they found writings that expressed heartache, anger, and resentment over a breakup
Although they had only three dates, Siesser felt a strong connection with his new girlfriend, and when she abruptly broke off the relationship with him, Siesser was depressed for six months and sought counselling.
The affidavit states that Siesser wrote fictional stories about men exacting vengeance on ex-girlfriends. In one story, a man used a fertilizer spreader to lace a woman’s yard with asbestos, which ultimately killed her decades later. In another story, a man locked a woman in scuba gear in a submerged box so she would die when her oxygen tank was depleted.
The juvenile, whose name Siesser used to purchase the toxic chemicals, revealed in an interview with federal agents that the man had told him he ‘wanted to be an assassin and killed those who had wronged him in the past,’ including his ex-wife and ‘others.’
Prosecutors had previously said that they did not believe a public attack was planned.
Siesser’s attorney told the New York Times that the 48-year-old, a former teacher who had served in the military, has been struggling with mental health problems and expressed remorse.
A LinkedIn page associated with Siesser reveals that he served in the US Army for four years, later worked in customer support in the Netherlands, and most recently taught social studies at a high school in Higbee, Missouri.