Woman stabbed City banker partner after he said he had met someone else, court told

Evening Standard · collected 2026-09-16 · by Tom Place
Read the original at Evening Standard ↗

Summary

Joanna Cierpka, 51, was arrested on March 15, 2026, after police discovered her partner Henrik Slotsaa, a 52-year-old banker at Citibank in London, dead at their home. At the hospital, Cierpka admitted to killing Slotsaa and told jurors that she attacked him after he revealed he had met someone else at work. The article focuses on the circumstances leading up to the incident, including Cierpka’s unemployment, her depression, and Slotsaa’s relationship with a colleague named Aimee O’Shaughnessy.
Written by the local model on 2026-09-17, using this article's own text rather than the other coverage of the same event (that is the story summary below).

Signals How these are calculated →

Claims extracted
35
claim-shaped sentences
Uncertain
17%
6 of 35 hedged
Leaning
not political
takes no side on a contested political question
Correction & hedging signals
71.4
corrections and hedging in what we collected; not a measure of accuracy
Outlets on this story
1
Crime & Law
Narrative spread
1
articles carrying this framing
Analyzed 2026-09-17 · how these are computed

AI analysis (generated at analysis time, not now)

Story summary

Joanna Cierpka, a 51-year-old Polish national, was arrested on March 15, 2026, after police found the body of her partner, Henrik Slotsaa, a 52-year-old Danish banker from Citibank's London office in Canary Wharf. The victim was discovered dead at their home in Elephant and Castle, and Cierpka confessed to killing him while receiving medical treatment for her wounds. According to court testimony, Cierpka told hospital staff that she had killed Slotsaa, signing a note detailing this confession.

The prosecution claims that Cierpka's mental state was significantly impaired due to previous depression treatments and unemployment, which affected her self-confidence. Friends of the couple testified that they noticed changes in Cierpka after she lost her job around 2019, indicating that she had been struggling emotionally since then. The defense is arguing for diminished responsibility by establishing that an abnormality of mental functioning caused her to kill Slotsaa and substantially impaired her ability to understand her actions.

Written for “Stabbing of Banker Over Infidelity” on 2026-09-17, grounded in this article and the 0 other(s) covering the same event.
Why this leaning score
This article does not take a side on a contested political question, so it has no leaning score. That is an answer rather than a gap: a match report or a rescue can be warmly or critically written without being left or right, and scoring it anyway is how approval of a subject gets recorded as a political position.
No political leaning scored for article 14393 · logged 2026-09-17

Story

📰 Stabbing of Banker Over Infidelity
Crime & Law · 1 article(s) covering the same event. This is the one the site leads with.

How this is being covered How these are calculated →

Article leaning vs. publisher reliability
Source leaning vs. consistency

Compared with similar articles

Nothing to compare against. No article is close enough to this one for the pipeline to have linked or judged the pair.

Publisher

Evening Standard · 641 article(s) · 3 correction(s) detected
Running correction rate · 3 correction(s)
2026-09-16
Chelsea injury update: Joao Pedro, Reece James, Moises Caicedo latest news and return dates
2026-09-11
Liverpool injury update: Bradley Barcola, Cody Gakpo, Milos Kerkez latest news and return dates
2026-09-10
Chelsea injury update: Levi Colwill, Moises Caicedo and Marco Palestra latest updates and return dates

Who wrote this

Tom Place
15 article(s) here · 1 carrying a prediction
🔮 William, Harry, Charles, Prince Philip and the Earl walked behind Diana’s coffin in a funeral procession through central London to the funeral service at Westminster Abbey.
🔮 A man who missed his train and threw a fatal punch to the face of an railway worker has been told he will be detained in hospital indefinitely.
🔮 In the following days they exchanged WhatsApp messages, and Cierpka said that she thought that Mr Slotsaa had had enough of her, and she thought they would soon be having a serious conversation about the future of their relationship, the prosecution said.
🔮 Some rains running to and from these stations may be cancelled or delayed, with disruption expected until around 1pm.
🔮 While the problem has been fixed, experts say the knock-on disruption to airline schedules will last for several days.
🔮 “The Government is devolving new licensing powers to the Mayor to help support pubs and nightlife.
🔮 The Mayor of London celebrated London’s position as the music capital of the world, with the London’s parks, arenas, and stadiums hosting some of the biggest stars this year.
🔮 The trust’s board has warned that the ability to deliver patient care could be affected by problems with its estate.
🔮 Early bird tickets for next year’s event, set to take place on September 5 2027, have already sold out.
🔮 Furious top brass have reportedly launched a strategic forum to investigate exactly what happened, with more uniformed officers set to be quizzed in relation to the probe.
Also by Tom Place
Nothing else under this byline is closely related to this article, so these are simply their most recent.
All 15 articles by Tom Place →

Topics

Canary Wharf Citibank Danish London Polish

Subjects

Slotsaa PERSON · 11× Cierpka PERSON · 8× Lynn PERSON · 6× O’Shaughnessy PERSON · 5× Citibank ORG · 3× Kotynska-Lynn PERSON · 3× Danish NORP · 1× Henrik Slotsaa PERSON · 1× Joanna Cierpka PERSON · 1× London GPE · 1×

Narrative

The prosecution said that in order to prove diminished responsibility, the defence must establish that each of the following four things are more likely than not to have existed: that when she killed Mr Slotsaa, Cierpka was suffering from an abnormality of mental functioning; and that her abnormality of mental functioning arose from a recognised medical condition; and that her abnormality of mental functioning substantially impaired her ability to understand the nature of her conduct and/or to form a rational judgment and/or to exercise self-control; and that her abnormality of mental functioning caused, or was a significant contributory factor in causing, her to kill Mr Slotsaa.
framing: assertive · carried by 1 article(s) · first seen 2026-09-17
🔮 In the following days they exchanged WhatsApp messages, and Cierpka said that she thought that Mr Slotsaa had had enough of her, and she thought they would soon be having a serious conversation about the future of their relationship, the prosecution said.

Claims (35 extracted, 6 hedged)

Joanna Cierpka, 51, was arrested on March 15, 2026, when police found the body of 52-year-old Henrik Slotsaa at their home in Elephant and Castle after being called to the property having been alerted to welfare concerns. asserted
police → arrest → concerns
Danish national Mr Slotsaa, who worked as a banker at Citibank’s London office in Canary Wharf, was found dead in a bedroom, and it was clear he had been dead for some time, Danny Robinson KC, prosecuting, said. asserted
KC → work → time
Read More Polish national Cierpka was arrested and taken to hospital for treatment for her wounds. asserted
Cierpka → read → wounds
At the hospital she told a member of staff: “I killed my partner”, which was recorded in writing, and she signed and dated the note, jurors were told. asserted
jurors → tell → note
Stephen Lynn and his wife Anna Kotynska-Lynn said they became friends with the couple in about 2019, and Mr Lynn said at that time the defendant was the “life and soul of the party”, the prosecution said. asserted
prosecution → say → party
Cierpka was made redundant which affected her self-confidence, and she had previously received treatment and medication for depression, the court heard. asserted
court → make → depression
They met up for the defendant’s birthday on January 17, and Ms Kotynska-Lynn thought that although she was trying to be more like her old self, she was struggling. asserted
she → meet → self
In the following days they exchanged WhatsApp messages, and Cierpka said that she thought that Mr Slotsaa had had enough of her, and she thought they would soon be having a serious conversation about the future of their relationship, the prosecution said. asserted
prosecution → follow → relationship
After her arrest, Cierpka told a psychiatrist that in December 2025 Mr Slotsaa had told her he did not love her anymore, and that on her birthday he told her that he had met someone else at work. asserted
he → tell → work
In late February or early March, Mr Lynn and Ms Kotynska-Lynn saw Mr Slotsaa briefly on his own and he mentioned to Ms Kotynska-Lynn that Cierpka was in a bad way, and that he had started to plan for a life after her. asserted
he → see → her
By that stage, Mr Lynn knew that Mr Slotsaa had been, in Mr Lynn’s words, “flirting” with a work colleague called Aimee O’Shaughnessy, the court heard. asserted
court → know → colleague
On March 8 Mr Slotsaa told Mr Lynn that he thought Cierpka had found out about Ms O’Shaughnessy, because she may have been looking at his phone. uncertain
she → tell → phone
Mr Lynn said that on the same day Cierpka just sat on her phone, scrolling, and he described the atmosphere as “strained.” asserted
he → say → atmosphere
Ms O’Shaughnessy started work at Citibank in September 2025 and first met Mr Slotsaa at a work event on November 12, and they struck up a friendship. asserted
they → start → friendship
In December they had lunch together and they swapped numbers. asserted
they → have → numbers
Throughout January 2026 Mr Slotsaa and Ms O’Shaughnessy met up for lunch on a number of occasions. asserted
Slotsaa → meet → occasions
Mr Slotsaa told Ms O’Shaughnessy that things were not great at home, and he told Ms O’Shaughnessy that he liked her, the prosecution said. asserted
prosecution → tell → her
She said that she did not want to complicate things by starting a relationship with him. asserted
she → say → him
According to her, he was fine with this, Mr Robinson added. uncertain
Robinson → accord → this
In the week of March 9 to 13, before the police found his body, his work colleagues became increasingly concerned about Mr Slotsaa’s welfare because he was absent from work and they could not contact him. uncertain
they → find → him
On March 13 one of Citibank’s security employees went and called up to the flat on the intercom and spoke to Cierpka, who said he had gone out. asserted
he → go → Cierpka
Forensic pathologist Dr Ashley Fegan-Earl conducted a post-mortem examination on March 18 and said death occurred around March 9, although he stressed that he could not be precise about when Mr Slotsaa died. uncertain
Slotsaa → conduct → March
The examination revealed there were 14 separate sharp force injuries. asserted
examination → reveal → ?
He noted wounds to the face, neck, arms and legs. asserted
He → note → face
There were three injuries to the neck, one of which was potentially fatal on its own, jurors heard. asserted
jurors → be → own
There were also wounds to the backs of both knees that may have represented an attempt at dismemberment, the prosecution said. uncertain
prosecution → be → dismemberment
The prosecution said that in order to prove diminished responsibility, the defence must establish that each of the following four things are more likely than not to have existed: that when she killed Mr Slotsaa, Cierpka was suffering from an abnormality of mental functioning; and that her abnormality of mental functioning arose from a recognised medical condition; and that her abnormality of mental functioning substantially impaired her ability to understand the nature of her conduct and/or to form a rational judgment and/or to exercise self-control; and that her abnormality of mental functioning caused, or was a significant contributory factor in causing, her to kill Mr Slotsaa. asserted
her → say → Slotsaa
Psychiatrist Dr Penelope Brown, who was instructed to examine Cierpka by the defence, formed the view that at the time she killed Mr Slotsaa, Cierpka was suffering from an episode of severe depression with marked suicidal tendencies, such that it represented an abnormality of mental functioning from a recognised medical condition, jurors heard. asserted
jurors → instruct → condition
In Dr Brown’s opinion, the depressive episode impaired her abilities to form a rational judgment, and to exercise self-control. asserted
episode → impair → control
As a result, according to Dr Brown, the defence of diminished responsibility is available to Cierpka, the prosecution said. uncertain
prosecution → accord → Cierpka
The prosecution instructed another psychiatrist, Dr Shamir Patel, to examine Cierpka who concluded that she was not suffering from diminished responsibility when she stabbed Mr Slotsaa. asserted
she → instruct → Slotsaa
Although Dr Patel agreed that at the time of the killing Cierpka was suffering from depression, which is an abnormality of mental functioning arising from a recognised medical condition, he did not accept that it substantially impaired her ability to form a rational judgment, or to exercise self-control, the court heard. asserted
court → agree → control
Dr Patel also disagreed that her depression provided an explanation for her conduct. asserted
depression → disagree → conduct
In his professional view, the killing happened because she was angry with Mr Slotsaa, and jealous of his friendship with Ms O’Shaughnessy, set against a backdrop of the deterioration of their own relationship and her use of alcohol, the prosecution said. asserted
prosecution → happen → alcohol
The trial continues. asserted
trial → continue → ?
💬 Give feedback
🕘 History 🎫 Support