Mary Ann Cotton (1832-1873) was Britain's most prolific female serial killer, who poisoned over a dozen husbands, lovers, and children with arsenic in Victorian England. Her crimes went undetected for decades because arsenic was commonly used in household products like soap, wallpaper, and medicine, and because Victorian women were typically seen as caregivers rather than killers. The case was only solved through the Marsh test, a chemical procedure that detected arsenic in victims' bodies, leading to her conviction and execution in 1873. This case prompted significant changes in poison laws and forensic investigation methods.
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The Original Black Widow: Mary Ann Cotton | Murder Maps - Season 4 Episode 2Added:
For many a centuries, Britain was a dangerous [music] place.
It was a magnet for the very worst kind of people.
Jack the Ripper dominated the headlines.
But he wasn't the only killer around.
Murder was a foot.
The fear of death [music] was everywhere.
But police had their work cut out to track the culprits down.
In this series, we'll be [music] investigating some of the country's most notorious and intriguing crimes.
Female defendant.
Sexual intrigue, vicious murder, as well as the latest technology fed the nation's insatiable desire for gruesome stories of Britain's dark side.
>> West Auckland in 1871 was a thriving mining town in the north of England.
Its importance, like other towns in the area, could not be overstated.
Coal permeated all aspects of Britain.
And those that mined it were fueling an empire.
Dark and dangerous work, low wages, and fatal health [music] conditions meant life was tough and short.
This hardship brought the inhabitants of West Auckland together.
But living among them was one of the worst serial killers in British history.
Mary Ann Cotton poisoned more than a dozen of her friends, lovers, and children.
A murderer who escaped justice for decades until the efforts of one man brought her terrible [music] crimes to light.
Thomas Robinson was a highly regarded citizen of West Auckland.
He and his wife Margaret were landowners, grocers, [music] and Thomas was also the deputy coroner.
He was the overseer of poor relief in West Auckland and was in charge of admissions into the local workhouse.
Workhouses in England provided a home and employment for the destitute.
The conditions there were often harsh.
By the 1870s, the workhouse had become a dreaded institution.
The workhouses in Victorian England were the absolute last resort for people who were really down on their luck, really impoverished. [music] The Victorian workhouse was a place that every working man and woman dreaded.
It was regarded as a prison.
You would get a roof over your head, you'd be fed, and you'd be clothed, but in return for that, you had to provide your labor, and it was incredibly hard labor.
They didn't want to encourage people who were in poverty into the workhouse where they'd be provided with a bed and food.
They wanted to discourage people going into the workhouse, so it was deliberately organized so that it was the bare minimum for survival.
Conditions there were often harsh.
By the 1870s, it had become a dreaded institution.
Thank you, Mrs. Cotton.
Good morning, young man.
Answer Mr. Riley, Charles.
Not a word since his father passed.
>> [music] >> I have been thinking on your situation.
Mrs. Cook over at St. Helens, perhaps you've met her son.
Well, Mrs. Cook [music] has suddenly contracted smallpox.
The family is seeking a nurse.
Forgive me, sir.
It's all right.
No one else has shown me such kindness.
So, I shall inform the Cooks.
The son, he's a farmer.
Aye.
And a good one, too.
You can take the boy with you, of course.
Course.
Only the care of a child is not an occasion in itself.
If I'm to save poor little Mrs. Cook, I can hardly be looking after the boy.
He has no other family?
An uncle down south.
A road, but he's own flesh and blood.
I asked the neighbors, but they'd rather they weren't fed.
Could he not [music] be taken into the care of the parish?
The workhouse? I know of the rules.
[music] We do not take unaccompanied children.
This is exceptional. [music] On account of poor Mrs. Cook.
It's the board's position.
Mr. Riley, are you telling [music] me if you went to that workhouse and said, "Take this boy. Care for this [music] boy."
They wouldn't do what you say. A man of your standing.
It's a kindness I [music] wouldn't forget.
I'm sorry, Mrs. Cotton.
He keeps me [music] from my work.
From taking on an honest lodger.
How am I to live? [music] He's not my boy.
Every child is a present from God.
Regardless of the path that brings him to us.
Thank you for the tea.
He'll not get up to be a man.
The Cotton's all of them sickly.
He won't be long.
Mary Ann Cotton wanted her stepson out of the way.
And if it wasn't to be the workhouse, she'd have to find another solution.
Mary Ann Cotton was born in County Durham in 1832.
The Industrial Revolution was underway.
In the northeast [music] of England, coal mining was transforming the landscape and people's lives as well.
Those tiny >> [music] >> colliery villages in the east of Durham in the Victorian period were absolutely horrendous places to be brought up.
At the time, the northeast was a real hive of industry. There was shipbuilding, there was mining. This was the Industrial Revolution and and life was was getting incredibly fast-paced.
People would move around to follow work opportunities.
The impacts of the Industrial on that area meant that more and more people were taken away from the countryside and being crammed into sort of what can only be described as slum conditions.
It was pretty brutal existence.
Because of the rapid industrialization at the time, you had exponential growth of places like these tiny mining villages. They would double or triple in size in absolutely no time at all.
Towns and villages grew up really around the pits on where the mine shafts were located.
Mary Ann's father was a miner.
He died young after falling 150 ft down a mine shaft.
He'd been a bound worker, tied by contract to one mining company.
And their claim over him continued even in death.
After the accident which killed him, Mary Ann's father was shipped home in a sack, stamped property of the South Hetton Coal Company.
Her mother remarried.
The family moved.
Death, marriage, relocation. It was a pattern repeated throughout Mary Ann's life.
But with one crucial difference.
Mary Ann was just a girl, 9 years old when her father died. She had to do as she was told.
But in future, nobody would claim her.
Nobody would control her.
She would be in charge.
Mary Ann first married at the age of 19.
Her husband was a man named William Mowbray.
Mary Ann was already pregnant, and the couple had a discreet wedding 20 mi from home.
Perhaps eager to escape gossip more permanently, they then moved to Cornwall.
They had a daughter, Margaret Jane.
She died in 1860.
Further children followed, two more girls and a boy.
None would live long, nor would Mary Ann's husband. William Mowbray had been working on a steamship, but fell suddenly ill while on leave.
He died at home in January 1865.
Typhus fever was blamed.
>> [crying] >> People would get ill quite regularly.
Standards of hygiene at home and at work weren't anywhere near what they are today. Life was quite harsh, working conditions were quite dangerous, and to end up as a woman on your own was was quite something and and you really had to make sure that that you would be looked after.
Her first husband, William Mowbray, died. Mary Cotton received about £35.
Now, add on a another couple of noughts for Mondays, so that's £3,500.
Quite a significant sum.
Which would have made quite a lot of difference.
Life insurance was reasonably common at that time, but there is an exception in that the insurance industry does not generally insure children, particularly the young children.
The government became suspicious that people would [music] be putting life insurance on their tiny children and then killing their children to get the life insurance money.
There was some concerns amongst the >> [music] >> middle classes looking at some of the behavior of the working classes around life insurance. So much so that in 1850, there were limits placed [music] on the amount that you could insure children under the age of three.
Few in the Victorian era were spared experience of childhood [music] mortality, especially the poorest.
Scarlet fever, smallpox, tuberculosis, [music] typhus, there was no end it seemed to the illnesses to which a child might succumb.
In mid-Victorian times, [music] there wasn't any NHS as we know it today.
Uh no National Health Service, so people had to pay for the doctor.
You'd have epidemics [music] of things like cholera and particularly typhoid would just sweep through these villages and take away dozens of people.
There was even a saying which was pretty common throughout the country [music] in Victorian times that you weren't really a mother unless you'd lost one.
That was how bad [music] it was.
Doctors were often overworked and under-qualified. [music] All too often where their treatments weren't useless, they were deadly.
Their patients were always coming and going [music] in search of work, a fresh start, or perhaps just to forget past troubles. [music] In those days, you didn't have to travel far and you could disappear.
You could start again.
They were the perfect conditions for a serial killer.
Settling in Sunderland, Mary Ann found work as a nurse at the city's infirmary.
It was there she met a patient named George Bull.
After his recovery, the couple married.
It was less than 7 months after the death of Mary Ann's first husband.
George, however, proved a disappointment.
He described himself [music] as an engineer, but was probably just another stoker on a steamship.
He was soon too ill to work, [music] suffering with frequent paralysis.
He relied solely on his new wife.
It was a burden Mary Ann could do without.
A year on from the wedding, George died.
Three doctors had been consulted. Each was baffled by the young man's ongoing sickness and surprised at how quickly the end came.
Nevertheless, Mary Ann escaped [music] suspicion.
Cholera and typhoid fever were blamed instead.
Once again, Mary Ann pocketed the insurance [music] money.
But that was nothing compared to the thrill of getting away with murder.
She had outwitted not one, but three medical men.
How powerful she must have felt.
But as the years went by, it was no longer enough to enjoy this superiority in secret.
She had to flaunt it.
She began openly predicting the deaths she would cause.
What Mary Ann was trying to do was to put it in the minds of people that this person who she was nursing was iller than they thought.
It's said that some serial killers want to be caught, but I don't think it's so much that they they want to be caught and apprehended. It's the recognition that they want. They want the reward for for actually doing the the terrible things that they've been doing. They they've probably been seeing the case in the newspapers. They've probably been hearing about gossip [music] in the the local community, and they feel quite smug that they're the one that's behind this. And I think sometimes that that need for recognition will [music] often lead to their downfall. Having poisoned so many of her husbands and children, and people might think, >> [music] >> well, perhaps she thought that she was untouchable and she'd never be [music] convicted.
>> [music] [music] [music] [music] [music] [music] >> Yeah.
>> Sit up a [music] bit.
>> [music] >> That's a good boy.
Better soon.
>> [music] [music] [music] >> Doctor?
The coughing boy.
Gastric fever.
That poor woman.
It was not your fault.
It was the board's decision.
No unaccompanied children.
And a sickness like that, they would have taken him in the workhouse just as quick as at home.
Nobody could have predicted this.
She did.
What?
Doctor, Doctor Kilbane.
I must speak with you.
Arsenic was everywhere in Victorian Britain.
It was used to make soap and medicine, cosmetics, and wallpaper.
But it could also be bought in a powder from the local shop.
I compare it [music] to bleach today.
It's something that was available pretty much everywhere. It was something that was used by everybody around and about their houses. It's a metallic poison. It comes from when lead is being manufactured and developed. And arsenic was a byproduct of that, and a lot of arsenic was used for all sorts of different purposes in Victorian times.
It was used in the manufacture of dyes.
You could even buy soap, and the adverts actually say, "This soap has got arsenic in it, and this will sort of improve your complexion and do do wonders for you."
>> Playing [music] cards, fireworks, wallpaper, furniture. You you'd even find it in sweets to give them a distinctive green color.
Neither taste nor odor to raise suspicion. Arsenic was the perfect poison.
In large doses, it killed quickly.
Smaller amounts prolonged the agony.
Either way, its effects could easily be mistaken for other maladies common to the era.
It wasn't just Mary Ann Cotton who found the poison useful for dispatching unwanted husbands.
In 1889, Florence Maybrick was faced with divorce and ruin. When suddenly, her husband became ill and died.
She was charged for murder when traces of arsenic were found in his body.
It was discovered that she'd been soaking fly paper [music] in water to extract the arsenic, which she claimed was for cosmetic purposes.
She was sentenced [music] to death.
But this was commuted to life imprisonment when it was found that the cause of death was self-medicated strychnine by James himself.
She escaped the death penalty and was released in 1904.
In the mid-19th century, however, the government began to crack down. Sales of arsenic were restricted.
And new chemical tests were devised that could detect its presence in dead bodies.
Arsenic's reign as poison of choice was coming to an end.
With her heinous acts going undetected and her victims safely buried, Mary Ann would move on to a new town for a fresh start, as she had so many times before.
Watching plus life during this period, meant that you could quite easily wipe the slate clean and just go and start again in another town or another city.
Communities tended to be smaller, closer knit, And you wouldn't necessarily know about people from other communities. So, it would be quite possible for Mary Cotton to move from community to community and for her story and perhaps suspicions not to catch up with her.
James Robinson [music] was a Sunderland shipwright who recently lost his wife.
With five children under 10, he needed help raising his family. So, he placed an advertisement for a housekeeper.
It was answered by Mary Ann.
Shortly before Christmas 1866, she moved into the Robinson household.
By the following April, all the Robinson children were dead.
Their father found a source of comfort in his grief.
And Mary Ann was soon pregnant.
Robinson was a decent man and did the decent thing.
He proposed.
Marriage to Robinson would be a step up in the world for Mary Ann.
She would not let anything get in the way.
During the courtship, her mother fell ill.
Mary Ann was called upon as nurse.
The poor woman died within days of Mary Ann's arrival.
The future Mrs. Robinson was free to return to Sunderland.
Three months after the wedding, Mary Ann gave birth to a baby girl. But by then, Mary Ann had what she wanted.
The child was no longer needed.
She died of convulsions within weeks.
Death seemed to follow wherever Mary Ann went.
Perhaps some were natural, it's hard to be certain.
But the deaths never caused an inconvenience. They always removed distractions and complications from Mary Ann's life.
And the symptoms were always [music] remarkably similar.
There is nausea, there are great stomach pains, horrendous diarrhea, and tremendous thirst. Other symptoms would include headache, confusion, sickness.
You would have these telltale white lines on your fingernails and toenails, which are called Mees' lines, which today are an absolute giveaway to doctors that you're suffering from some kind of heavy metal poisoning.
Mary Ann Cotton's marriage to her third husband was coming to an end.
He'd found out that she'd been stealing from him.
Her latest husband had never have imagined the depravity of her real crimes.
James Robinson discovers some 50 or 60 pounds that Mary was supposed to bank has not been banked, and she's run up debts of about 60 pounds. We don't know for sure exactly what Mary Ann Cotton was doing with the money that she stole from James Robinson, but what we've got to think of at the time is what's going on more broadly in society. [music] You've got the the developments of consumer culture, you've got shops [music] popping up here, there, and everywhere selling nice things, and many of the the newspaper articles written back at the time say that Mary Ann liked to buy nice things. She she liked to be surrounded by >> [music] >> consumer luxury goods.
Married couples tend to argue about money, and if it's fairly obvious that your new wife has been stealing [music] money from you, then that's going to be a source of tension at the very least.
He's expecting that there's around about £21 [music] in his bank account, but actually there was only 22 shillings.
And that wasn't the extent of her criminality, >> [music] >> essentially. She was pawning household items like furniture and like clothing as [music] well. So, she really was bleeding this man dry.
>> [music] >> Robinson threw Mary Ann out.
Probably saved his life.
Mary Ann had been trying to convince him to take out life insurance.
It's obvious what she had planned.
Doctor!
Doctor Kilburn!
I must speak with you.
Mrs. Riley's not taking sick, I hope.
His concerns Master Cotton.
You treated the boy.
I'm on my way there now.
>> I saw Master Cotton not three [music] days ago, Doctor.
He was the very picture of health.
His sickness was sudden. But many maladies are. Sudden.
So, unpredictable then. Yes, I suppose.
Have you issued the death certificate?
Not yet. In that case, Doctor, I want you to come with me at once. But I have patients to see. Mrs. Cotton is expecting me.
>> She can wait. Please.
William Byers Kilburn was the local physician who had seen Charles Cotton in the days before his death.
Kilburn postponed issuing a death certificate. An inquest was planned.
And an autopsy was carried out.
Charles Edward Cotton's autopsy happened on the kitchen table in Mary Ann Cotton's house.
Inquests at that time were not normally held in a formal court of law such as we have. Generally, it was in the local pub.
They really were a kind of rough and ready open forum kind of public justice.
And there would be a jury, a jury of men who would be summoned by the coroner.
Now, this jury, they would hear evidence from witnesses, they they would hear medical evidence, and they would come to a conclusion as to how a death had actually come about.
The inquest into the death of Charles Edward Cotton declared the boy had died of natural causes.
Once again, it seemed that Mary Ann had escaped.
Mr. Riley.
Mr. Riley.
Mrs. Cotton.
I just wanted you to know I bear you no ill will.
My concern was only ever for the boy.
May he rest in peace.
And raise in glory.
Good day, Mrs. Cotton.
The parish will do its duty, though.
Here for the funeral.
Mr. Cotton shall not burden you any further.
I'm just a penniless widow, Mr. Riley.
We can't all afford grand memorials.
This funeral will be paid for from the rates.
With all the proper dignity that boy deserves.
She was smiling.
As though she'd won some great prize.
An inquest.
Who smiles at an inquest?
Is it not time to let this be?
That boy deserves justice. He deserves peace.
This is becoming an obsession.
People are beginning to talk. What people?
They're saying you forced a grieving mother to face an inquest.
To have her son cut up right in front of her on the kitchen table. He wasn't her son, and she made that very clear. We've had half our usual custom, Thomas. Ah, it's a lull. We'll ride it out.
But for how long?
People remember.
Might Thomas Riley be coming after me next time?
We've all of us lost one.
And you don't want to be going back down the pit.
Not at your age.
We're closed.
Thomas?
Thomas?
Who do you think this is, Annie?
Mrs. Cotton killed that boy, Margaret.
Dr. Kilburn's here to help me prove it.
Mary Ann Cotton had been thrown out of the Robinson home for theft and deceit.
With a legacy of death in her wake, things were looking bleak for the heartless poisoner.
She seemingly had nothing.
But she was not homeless for long.
Within months, she was introduced to her fourth husband, Frederick Cotton.
He was another pitman, a widower with two young children, just Mary Ann's type.
He needed somebody to look after the two children. She was destitute and looking for a man to move in with so that she could survive cuz otherwise she'd have been on the streets. It's very, [music] very difficult for a woman on your own to survive in Victorian England. It's very difficult to have any money, to have any [music] employment that that's going to allow you to stand on your own two feet.
This was a very [music] sexist society, Victorian England. If you didn't have a man, a husband, you had very low status.
With him, I think [music] she saw a chance to get married again, settle down again, establish herself again.
They married on the 17th of September, 1870.
The following April, they moved to West Auckland.
Unlike James Robinson, Cotton was not [music] wise enough to refuse his new wife.
He took out life insurance on himself and his children.
Within a year, they were all dead.
She's now got rid of four husbands and numerous [music] children. By now, the number of child deaths is about 11 or 12.
Looking at [music] child homicide in the 19th century, it wasn't as rare as we might think. It certainly isn't as [music] rare as it it is today. These people were having these lives that were so difficult and so tragic that actually another mouth to feed would plunge [music] them further into poverty. But for Mary Ann, killing her children was was nothing >> [music] >> like this. That was not the reason why she killed her children. She killed her children because they were an inconvenience to her.
Mary Ann already had her eye on husband number [music] five, an excise officer named Richard Quickman.
Rumors in [music] the village whispered she was already pregnant with his child.
But there would [music] be no wedding.
Have you performed this test before, doctor?
I have seen it done, or explained, at any [music] rate, and I have read on it.
The boy's stomach.
The Marsh test is a simple chemical procedure.
The sample to be tested is dissolved in a solution of hydrochloric acid.
A strip of copper is then inserted and observed. If it gains a dark coating, it indicates the presence of arsenic.
That was the test Dr. William Kilburn administered in West Auckland on the 17th of July, 1872.
I'll summon the sergeant.
>> [music] >> Mary Ann was remanded into the custody of Durham Jail while investigations continued.
>> [music] >> They called in a much more highly qualified doctor >> [music] >> called Scattergood, Dr. Scattergood from Leeds, who was a proper toxicologist.
And he did a series of tests >> [music] >> and found that there was arsenic all over Charles Edward's body. There was a tremendous amount of publicity building around the case. And when it was discovered so many other children had died, [music] husbands had died, lover had died, then all this cumulative evidence, excessive evidence, all builds up as part of the case against her.
Charles Edward Cotton's [music] newly buried remains were exhumed.
As were those of several other suspected victims.
In every case, [music] arsenic was found.
Enough to kill.
>> [music] >> Mary Ann was put on trial for the murder of Charles Edward Cotton.
She insisted on her innocence. [music] Her barrister suggested any poisoning had been accidental caused by tainted medicine, the [music] Home's green wallpaper, or the soap used to clean the beds.
But once the jury [music] heard evidence of Mary Ann's past, of the deaths that followed everywhere she went, any doubts [music] evaporated.
Nobody ever expected [music] a woman to do this kind of thing. This goes against all of our expectations of who women are and how they should behave in Victorian England. They're the carers, they're the nurturers.
Another reason why, because she's not in the limelight, that people don't notice [music] her. She's always the nurse, she's the dressmaker, she's the stepmother looking after the [music] children. By the time she'd killed, possibly, four or five people, [music] she was so expert, she knew how to conceal it.
She chose to create [music] and destroy multiple manifestations of the family, that one institution that constrained her. She had in her mind a kind of ideal life that she wanted to live. [music] As a wealthy woman who didn't have to do any work in a big house. Essentially, what we're looking at here [music] is somebody who's killing as an emancipatory effort, albeit a dysfunctional and antisocial [music] one. She's the one who's in control in the institution that is essentially deciding on how she lives her life.
With the knowledge that she'd killed over a dozen people, possibly more over time, the jury had no sympathy for this cold-hearted killer.
After retiring for 90 minutes, they returned with their verdict.
Mary Ann Cotton was found guilty.
On the 24th of March, 1873, she was hanged at Durham County Jail.
The executioner was an elderly man notorious for incompetently using the short drop.
Her executioner was William Calcraft, one of the worst hangmen ever who lived.
He favored the short drop method of hanging.
The advantage of that is that you don't accidentally pull the head off the victim.
That was good from the point of view of the hangman because it meant that the clothes of the victim were not covered in blood.
And traditionally, these clothes were inherited by the hangman who would then sell them off as souvenirs. With Mary Ann Cotton, he gave an even shorter drop than usual cuz it was only a 2-ft drop.
Which meant that her head and shoulders were still above the trapdoor.
He couldn't go underneath and swing on the legs, and so he reached over and pushed down on the shoulders to strangle her.
And from the convulsions, uh she lasted about 3 minutes before eventually she lost consciousness.
The most prolific woman serial killer in British history died slowly strangling on the rope.
It was a kind of end that Mary Ann Cotton gave to her victims.
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