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Criminal Law: Murder by Poison

Colleen is an attorney in the United States, and a solicitor on the roll in England and Wales.

Historical Overview

Throughout history, there has been an endless fascination with murders committed by poisoning. Perhaps this interest results from the fact that, once a likely perpetrator and victim have been designated, complex questions arise on a human level.

To begin, what drives an imputed defendant to desire the death of a fellow human being with such zeal as to prepare a drink or dish in a way as to bring about his demise? Indeed, there can be no deeper degree of premeditation. Both the definite guilty mind, "mens rea" and a decisive act, "actus reus" are clearly interwoven.

In all probability, the most astute archaeologists will never succeed in ascertaining when this method began to be deployed. Still, we do know, certain herbs and plants, ingested by themselves or amalgamated with others, were utilized for this purpose.

In ancient Egypt, cats were deployed to eat foods prepared for pharaohs. If the cat enjoyed the dish, or at least survived after ingesting a small amount, the dish in question was deemed acceptable for royal consumption. (Later, European royal circles would make use of human food tasters for this same purpose.)

No humane being, past the thoughtless age of boyhood, will wantonly murder any creature which holds its life by the same tenure that he does.

— Thoreau

During Roman times, among others, Emperor Claudius was believed to have been poisoned by his fourth wife via a dish of mushrooms. When he began to choke, due to the first effects of the toxin, she pretended to do all she could in order to alleviate his distress.

She happened to have a feather at hand which she promptly pushed down his windpipe, in a seeming attempt to allay his distress. Unfortunately for this emperor, she had first saturated this feather with the same type of poison.

Later, the Borgia and Medici were reputed to have brought about the countless deaths of those obstructing their wishes or power, by use of poisons in various forms. This is not, by any means, to imply that the use of lethal chemicals was, or ever has been, most prevalent in this region. As the cases discussed in this article will show, their abuse has proved global.

Below we discuss the cases of four infamous poisoners: George Trepal, Henri Girard, Mary Ann Cotton, Velma Barfield.


Poisoner George Trepal

The majority of poisoners target a specific victim. Still, there are those for whom lack of direct access to the designated prey, combined with an absence of concern as to who might be injured by ingestion of the toxic substance deployed overrides any remnant of conscience. This occurred in the case of George Trepal, (hereinafter T) a Mensa member who squandered his intellect on destructive activities.

The Carrs, T.s neighbours, lived as an extended family, with various generations co-existing in various areas of the same household. Not surprisingly, this group as a whole generated a good deal of noise. Their dogs were not well-controlled; and the teenagers made no attempt to limit the volume of their music.

It is difficult to determine, in most cases, at what point a series of quarrels escalates into ongoing rage. Once this occurs, initially trivial issues transcend the bases of conflict, escalating into questions of respect and dignity.

If a pivotal moment can be found, it seems to have come about when teen-aged members of the Carr family, while washing their vehicles, were blasting their radios at full tilt. T. strode out of his home and demanded the level of volume be lowered. Overhearing the fracas, Peggy Carr, the boys’ mother, stepped outside and ordered her sons to do as T. had asked. In seeming compliance, the boys lowered the sound until both adults had gone back inside. At that point, they raised the volume, in flagrant defiance.

Despite their struggles with T., such was the openness of the community that many families, including the Carrs, often left their doors unlocked when they left their premises. Thus, when Peggy Carr found 8 bottles of coke-a-cola inside her front door, she viewed it as a gift and enjoyed it as such.

Then, suffering stomach cramps so intense as to require hospitalization, she felt no specific suspicion. Even after being told by doctors she had been poisoned, she asked over and over again who could have wanted to harm her.

Thallium and Arsenic

Thallium was traditionally used in rat poison. It is a soft metal element mostly used in electrical components. In the form of thallium salts it is tasteless, soluble and highly toxic; hence once dubbed the perfect poison.

Before coma and death the victim will experience, often over weeks or months, nausea, vomiting, diarrhoea, sever stomach pain, convulsions, cramp, muscle loss, migraine, loss of feeling, memory and vision, psychosis, sudden hair loss, and hallucinations. Arsenic has similar symptoms but impacts more upon the organs of the body; kidneys, liver and lungs.

Letter of Menace

In March 1988, after four months of agony, Peggy Carr died, her life support system disconnected, due to her family’s awareness of the futility of sustaining her anguished life. In June of the same year, an anonymous letter was sent to the family, advising them to leave the state in order to avoid vengeance. Then, over a year and a half after Peggy Carr’s death, in November 1989, it was determined that thallium had been the substance which had contaminated the 8 bottles of drink.

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Police Suspicion

Fortunately, the Carrs had kept the menacing letter. A clue to Trepal’s guilt was found in the fact that, in 1975, while working as a biochemist in a laboratory which manufactured amphetamines, he privately produced thallium, a bi-product of such drugs.

Apprised of this information, police soon began to focus on T. as the most probable suspect. Still, given no hard evidence, investigators realized they would need to move forward with caution. Thus, Detective Susan Goreck, (hereinafter G) took on the task, aware it might involve a number of subtle manoeuvres.

Her first step in gaining T.’s trust, she decided, was to meet him in a way which would seem unplanned. Therefore, while not a Mensa member, G. inveigled her way into a Mensa murder mystery weekend, arranged by T.’s wife. T. had written a leaflet describing the "modus operandi". This consisted of a note written to a family, after which they were poisoned.

During the weekend, G. chatted with T. to the extent that he gave her his contact details. A few days later, she dropped by his office, ostensibly to discuss the clues and solutions of the previous weekend. After that, gently pursuing their “friendship” in a purely platonic sense, G. ascertained T. and his wife were attempting to sell their home in order to free themselves from obstreperous neighbours. G. then convinced T. of her wish to buy a new home as part of a divorce settlement.

When this potential “fell through”, G. offered to rent the house, thus allowing T. and his wife to relocate to a quieter area.

Once ensconced in T.’s residence, G. was able to glean various bits of evidence, all of which combined and created a basis for the police to begin their open involvement. Perhaps the most damning item consisted of a powdered form of the poison thallium, combined with a capping machine which would enable its owner to open a bottle, contaminate its contents, then recap it in such a way that it would be all but impossible to detect. This information facilitated the police in arresting G. as the almost certain perpetrator.

Although Peggy Carr was the only victim of T.’s attack, various other family members suffered the aftereffects of thallium poisoning. T was sentenced to death for one count of first degree murder, and several other acts of attempted murder.

Peggy Carr’s son has written of the frustration of waiting for his mother’s killer to be executed.

Poisoner Henri Girard

Girard (hereinafter- G.) was born in 1875 in Alsace-Lorraine then a province of the German empire. Well educated, he began what might have been a successful military career by joining the French regiment of the 4th Hussars. However, in 1897 he was dishonourably discharged. He continued to make a living as a petty swindler including illegal gambling and insurance fraud.

During this time G. who had an interest in bacteriology and poisons was experimenting with cultures of typhoid bacilli, (bacterium salmonella typhosa) both at his home and at a secret laboratory in the home of his mistress, Jeanne Droubin.

He went on to poison five family friends for profit.

Victim Louis Pernotte

G. moved to Paris where he founded a bogus insurance company, and was then banned and fined for deceptive practices. Undeterred, in 1909 he befriended an accomplice Louis Pernotte a wealthy insurance broker, who seemed willing to go along with G.’s scams.

It may have been a business arrangement or part of an elaborate plan to defraud; whatever, they signed into a joint life insurance policy payable to each-other upon the death of the other.

During 1912, G. invited the Pernotte family who were about to go on holiday to dine with him and his wife before departure. G. contaminated their food with a typhoid culture causing the family to become ill whilst on holiday. They assumed that the food eaten at their destination caused their illness.

When they returned, the family had recovered apart from Pernotte who was still suffering the effects of what he believed was bad food eaten whilst on holiday. We don’t know whether G. had intended to kill the family or simply to make them sick as part of a test within one of his medical experiments.

However, G. seized upon this opportunity to murder Pernotte. He initially voiced genuine concern to his friend and then offered to inject him via a hypodermic needle with a medicine that would cure his lingering sickness. Pernotte gladly accepted the offer, and shortly after receiving the injection he died.

Cause of death was diagnosed as typhoid, which was not unusual in the early 19th century. Hence G. received a sizable sum of money upon the insurance pay-out.

Victim Mr. Godel

In 1913, G. made friends with Mr. Godel. They agreed to make a two way (joint) insurance policy on each other’s life. Shortly after Mr. Godel accepted a dinner invitation after-which he became seriously ill with typhoid. He did not die, but later stated that he believed himself to have been poisoned by G.

Victim Mr. Delmas

In 1914, G. made friends with Mr. Delmas. Unbeknownst to Mr. Delmas, G. secretly borrowed his personal documents and insured his life, with a policy payable to himself. Not long after having dined together Mr. Delmas became seriously ill with typhoid. He did not die, and the doctor treating him later stated that he suspected illegal infection.

Victim Mr. Mimiche Duroux

Aware that using cultures of typhoid as a poison could not be relied upon to kill his victims G. began experimenting with poisonous mushrooms. Having created what he believed to be a lethal concoction he required a subject on which to test it, and decided upon his friend Mr. Duroux.

Once again without informing his friend, G. insured his life via a policy payable to himself upon death and then invited him to his home to dine. Shortly after the meal Mr. Duroux became seriously ill, but did not die. He later stated that he was suspicious that he had been poisoned and never met with G. again.

Victim Madame Monin

G. was now confident that he had developed a poison that would kill. He was also desperate for money and decided to go for a multiple insurance pay-out against his next victim. This was family friend Madam Monin. G.’s mistress Jeanne Droubin claiming to be Madam Monin insured herself with three different companies that would pay-out substantial sums of money upon her death, payable to G.

Shortly after; Madame Monin accepted an invitation to dine with G. and his wife at their home. During her return home Madame Monin fell ill in the street and died. Two of the insurance companies paid out on the policies but the third became sceptical in that the deceased was a young healthy woman.

They also believed that the woman who had taken the original medical examination prior to granting the insurance policy was an impostor; thus they refused to pay out, and instigated an investigation by the police.

Deathcap: Amanita phalloides

Deathcap: Amanita phalloides

The deathcap be the devil sprung from the earth wearing a fancy cloak.

— John C Earl

The Evidence

An autopsy revealed that Madam Monin had died from mushroom poison, later shown to be the Deathcap (Amanita phalloides). Further evidence included G.’s diaries containing entries such as the victim’s name and the word mushrooms.

His kitchen staff gave evidence that G. prepared the mushrooms eaten by Madam Monin and also washed the serving dish. Apart from the laboratories G. used at his and his mistress’ premises he had also purchased typhoid cultures and other toxic substances which were found at his home.

In 1921, after 3 years of gathering evidence including that of several bacteriologists and the exhumation of the victims’ bodies for further toxicity tests, G. was arrested and charged with two murders and 3 attempted murders. He was taken to the Fresnes Prison in Paris. Aware he was doomed, G. pre-empted the judicial process by ending his own life by swallowing a typhoid culture he had smuggled into prison.

However his wife and his mistress received life sentences.

This case brings to the fore the early scientific application of creating a poison rather than simply using a traditional element such as arsenic or an organic substance such as deadly nightshade. Here G, experimented in both creating and testing on human subject’s mixtures and derivatives of poisons that were both ingested and injected.

Fortunately contemporary scientific minds were able to expose his dastardly deeds.

Poisoner Mary Ann Cotton

Born in 1832, Mary Ann Cotton (maiden name: Robson) (hereinafter M.) is claimed to have murdered as many as 21 victims by arsenic poison. These included four husbands, the fourth “marriage” bigamous, and fifteen children which included eight of her own. It was the final four murders that are of significance as these deaths resulted in criminal charges and were all committed in the village of West Auckland, County Durham in the UK.

The deaths of the alleged earlier victims were never officially investigated. All the demises occurred in a similar manner, with the proceeds of insurance policies payable to M.

The West Auckland Murders

M. moved into 20 Johnson terrace at West Auckland in 1871 with her fourth husband Frederick Cotton, his two young sons Frederick Cotton junior and Charles Edward Cotton, and their own child Robert Robson Cotton. That year her husband Frederick was reported as staggering out of the house in gastric agony, and then dying in the street. The death was listed as caused by typhoid, a common disease at that time.

Shortly thereafter, M. collected the insurance pay-out from her husband’s policy. Within weeks her lover Joseph Nattrass who coincidentally lived close by, moved into M.’s home.

M. was an experienced and highly regarded nurse and soon found local employment caring for a Mr. Quick-Manning, who was recovering from smallpox. Due to his financial security and the fact of his having no children convinced M. that he would be an excellent marriage prospect. They soon became lovers. Unfortunately, she was still involved with lover Nattrass, and had three children to care for.

During a three week period in March 1872 her lover Joseph Nattrass, Frederick Cotton Junior her stepson aged 7, and Robert Robson Cotton their son aged 10, all died ostensibly from typhoid or similar illnesses. All three were insured in favour of M. Two weeks later M. announced she was pregnant by Mr. Quick-Manning.

Only one child, stepson Charles Edward Cotton aged 7, remained. It is not clear why his life was spared. Perhaps M. was receiving an allowance from the parish church to care for him until the age of eight. Nor do we know why M.’s relationship with Quick-Manning failed.

House of Mary Ann Cotton at West Auckland County Durham

House of Mary Ann Cotton at West Auckland County Durham

The Final Murder

Having collected the insurance pay-out for the three deaths M. was able to purchase and move to a larger three level property at 13 Front Street, West Auckland. Renumbered as 14 Front Street by the present owners, the house still stands and is a listed building

Despite those deaths which seemed to pervade M.’s every major encounter, such was the trust of the community in her nursing skills that she was asked to care for a woman afflicted with smallpox. This presented a problem in that she was still caring for stepson Charles Edward Cotton.

At about the same time as the above request, there are reports about a meeting between M. and a Thomas Riley who at the time held influence over whether M.’s allowance for Charles Edward Cotton would continue, and whether the boy would be accepted into the workhouse.

M. later claimed that Riley set conditions upon her that included compliance with his amorous desires. Riley later claimed M. had implied that the boy might soon follow in the footsteps of his brothers.

At any rate; six days after this meeting Charles Edward Cotton died. Local people said that the child was seen and heard screaming in agony at the top window of the house.

Riley believed that the death was suspicious and contacted the police. In addition he asked Doctor Kilburn to delay signing the death certificate until further examination. This in turn resulted in the insurance company withholding payment to M. on the boy’s life insurance policy.

Doctor Kilburn carried out a crude post-mortem on a work table in M.’s home, and retained the stomach, the contents, and internal organs. The inquest was held next day in the next door public house. Without any evidence to indicate foul play they concluded that the boy had died of natural causes. The following day the body was buried.

Riley continued to voice his dissent about the decision from the inquest. This resulted in Doctor Kilburn conducting further tests on the stomach contents and organs. He found arsenic in such quantity that he concluded that the boy had been poisoned. The next day M. was arrested.

Then, the bodies of all three children and Nattrass were exhumed and they all contained significant amounts of arsenic. Tests could not be made upon the deceased husband Frederick Cotton because his body could not be found, place of burial unknown.

After hearing the evidence offered at trial the jury took less than an hour to find Mary Ann Cotton guilty of the murder of Charles Edward Cotton. She was hung on March 24th 1873.

Poisoner Velma Barfield

A demoniac duo divided by time. By a macabre coincidence, a century after the October 1832 birth of Mary Ann Cotton, a similar female serial killer Velma Barfield was born in October 1932.

Both women used arsenic in order to dispatch their victims. In addition, many of those they killed, including their mothers, husbands, and lovers were people even the most venomous serial killers tend to regard as sacred. Both women were churchgoers, walking to their deaths as committed Christians.

Each execution was conducted in terms of the values of their times. Cotton was hung by a process re-instituted by hangman William Calcraft, according to which a convict would be strangled, by slow degrees, during a time period of 3 torturous minutes. Conversely, Barfield died via lethal injection, considered the most humane method of administering a sentence of death.

Velma Barfield, (hereinafter V.) grew up in a household where violence was a day-to-day misery. Baptized “Margie Velma Bullard”, she was generally called Velma. According to her memoir, one night, her father systematically broke each of her mother’s fingers. His violence extended to V. and to the rest of her siblings. Later, she blamed her mother for failing to intervene in order to halt these beatings.

In 1949, V. married Thomas Burke, perhaps as much to escape the familial hell as from genuine love. The couple produced two children in what seems to have been a fairly harmonious setting. Peace began ebbing away when the loss of her husband’s job exacerbated his tendency to drink. He became abusive to V. on both physical and emotional levels.

At around the same juncture, V. underwent a hysterectomy, causing her to have extreme mood swings. She was also diagnosed as bipolar, a clinical disorder characterized by mood fluctuations. This volcanic combination changed their marriage into an ongoing feud. In addition, V., having complained to her doctor of lower back pain, was prescribed the standard relaxant of the day: Valium.

Later V. stated she viewed them only as “little blue pills”. Sadly, far too soon, they became akin to blue devils.

The first indication of V.’s homicidal tendencies remained, for some while, undetected. The family home caught fire when both the children were at school, as their father lay in bed, presumably in a drink-induced slumber while V. was on errands. He died, and only in hindsight did their son, Ron, allow himself to recall his first touch of perplexity.

His Mother had, she claimed, been away when the spark was ignited, ostensibly by a lit cigarette dropped by her drowsing husband. Still, the question nagged as to why the firefighters needed to use axes to break down the door.

An insurance policy, though not large, was sufficient to cover the damage and repairs. Similar fires would occur twice more, with larger insurance pay-outs at hand.


As time passed, Barfield’s dependence upon not only Valium but a growing accumulation of a variety of tranquilizers, sedatives and painkillers increased. This became clear by her unsteady posture, slurred speech, and mounting expenditure for what she consistently referred to as her “medicines”. As she would later admit, she learned what she needed to say in order to obtain each medication.

In 1970, V. married a widower, Jennings Barfield. Within a year, he died of what may have been a genuine heart attack. Indeed, so many deaths seemed to haunt V.’s life that at one point, her son, by then a working adult feeling impelled to attend yet another funeral, commented to a colleague:

“You know, it’s the saddest thing; it seems whoever my mother gets close to, dies.”

In 1974, while looking after her ailing mother, V. took out a loan in her name, without her permission. When her mother became suspicious, V. found it expedient to rid herself of her. (While not confessing to all her alleged crimes, V. did later admit to having poisoned her mother.)

Given V.’s limited options, she began caring for the elderly and infirm. Often her minister, or a friend, would recommend her services to anyone who had voiced a need for a home care worker. At times, she resented being ordered about, treated as a menial. This seems to have provided a pretext, at least in her own mind, for her persistent poisoning. In truth she regularly forged checks in their names and feared the consequences if caught.

In time she became involved with Rowland Stuart Taylor. Always a churchgoer, her religious devotion enhanced her appeal for this man, the last of her victims. Having inveigled her way into his home, V. began forging checks in order to purchase her tablets.

When Taylor confronted her with this knowledge, she promised to pay him back. As had become routine by this point, unable to do so, she poisoned him in order to escape prosecution. (She already had a criminal record, due to forging checks and a prescription).

This time, however, her victim’s adult children requested an autopsy which revealed a deadly amount of arsenic within the decedent’s corpse. In 1978, she was arrested.

Arsenic was also found in the exhumed body of Jennings Barfield.

At trial, she did not deny her guilt. Instead, she pleaded the defence of diminished capacity combined with her bipolar condition. Her primary avenue of defence lay in her dependence on drugs. This, her attorney insisted on her behalf, had deprived her of any sense of reason or principle.

She was found guilty. Despite many appeals and support from eminent evangelists, she was executed by lethal injection on November 2, 1984.

© 2013 Colleen Swan


Colleen Swan (author) from County Durham on June 10, 2017:

Hi, Interesting point, but certain poisons such as cyanide and arsenic can be detected in blood. To find a modern day case you might look at Velma Barfield who murdered several people by this means.

lisa on June 09, 2017:

Id like to hear of a modern day story, because with the fact that for century's poisoning has gone on, and our environment is full of chemicals and toxins nobody believes you have been poisoned these days. Rape or robbed and beaten sure, but poison best call mental heath.

Colleen Swan (author) from County Durham on August 18, 2015:

Hi Stella, I also find books and movies intriguing. As it happens, The area in England where my husband and I live is a mere few houses away from Mary Ann Cotton's last home. As we live in a small village this is one of our few tourist spots, although a bit goulish. Thanks for your input. Colleen

stella vadakin from 3460NW 50 St Bell, Fl32619 on August 18, 2015:

I am an ID fan and watch a lot of shows about people being murdered. I am glad Mary Ann Cotton got caught. Hanging was too easy and quick for such a murderer. Awesome hub, voted up, sharing.

Colleen Swan (author) from County Durham on October 14, 2013:

Thank you for your comments. Thoreau using "humane" rather than human catches one's attention.

Dora Weithers from The Caribbean on October 14, 2013:

Thoreau's quote stayed on my mind while I read through these stories. Also the the first question you asked. I would like to have the privilege of hearing the answer from someone who actually did it. Thank you for sharing these cases.

Devika Primić from Dubrovnik, Croatia on October 11, 2013:

Criminal Law - Murder by Poison I have read and watched documentaries on similar cases it actually scares me to think of how another human being could go through such a plan and pretend to love a significant other and instead take their lives so painfully. No remorse!

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