Woman stabbed banker after he told her to 'kill yourself'

An unemployed business executive told jurors her banker boyfriend said 'Kill yourself already, you freak' before she fatally stabbed him. Joanna Cierpka, 51, is on trial at the Old Bailey for the death of Henrik Slotsaa, 52. Police found Mr Slotsaa's body at their shared home in Elephant and Castle, south London, on March 15, 2026. Ms Cierpka has pleaded not guilty to murder but guilty to manslaughter by reason of diminished responsibility.

Relationship breakdown and mental health struggles

Giving evidence on Wednesday, Ms Cierpka described how her relationship with Mr Slotsaa and her own mental health had deteriorated in the period leading up to his death. She told the court that Mr Slotsaa, a Citibank worker, had informed her he no longer loved her and had met someone else in January, on her birthday. Ms Cierpka stated she felt 'sad' after viewing text messages between Mr Slotsaa and the other woman on his phone but did not feel able to confront him.

The court heard that on February 19, Ms Cierpka had searched the internet for phrases including 'I don’t want to live anymore' and 'how to end it'. Her defence barrister, Jacqueline Carey KC, asked if Mr Slotsaa knew how she was feeling. Ms Cierpka replied that he did not understand depression, but she had repeatedly told him she did not want to live. She recounted Mr Slotsaa telling her she was only talking about it and not acting, and once stating that if she did so, the jointly owned flat would go to him. She also told the court he became annoyed when she scratched her eczema, saying, 'Kill yourself already, you freak.'

Defendant's actions and state of mind

In the days before Mr Slotsaa's death, Ms Cierpka said she had looked up his female co-worker online out of curiosity about the person she believed she was to be replaced with. When asked why she also searched for 'artery and neck', Ms Cierpka stated she had intended to kill herself. She told jurors she did not know if Mr Slotsaa was alive or dead when she searched for 'the highest penalty in the UK' on March 9. Ms Cierpka recalled going into the kitchen for a knife to take her own life, and the next thing she remembered was sitting in the living room with the blade on the coffee table. She stated she did not remember cutting Mr Slotsaa's neck in the bedroom or how he sustained injuries to the back of his knees, which were said to be consistent with an attempt at dismemberment. She described feeling 'mortified' as she had expected herself to be dead.

When asked why she did not call the police, Ms Cierpka said: 'I wanted to be dead before anyone found out.' In the week before Mr Slotsaa's body was discovered, she said she did not change her clothes. The court was told Ms Cierpka, originally from Poland, studied marketing and management and completed a masters in financial services before working for British American Tobacco. She met Mr Slotsaa through an online dating site and moved to London, eventually sharing a mortgage on their flat. She described their past as having an active social life with regular meals out and theatre trips. Ms Cierpka found the coronavirus lockdown 'extremely hard', stating it was like a dystopian 'Orwell book'.

At the end of 2020, Ms Cierpka was made redundant and struggled to find new employment while suffering from depression. She told jurors she had spent most of her life on the sofa, sometimes playing games on her phone or watching the ceiling. She stopped cooking, and Mr Slotsaa began buying ready-to-cook meals. In 2025, she spent five weeks in Greece with Dennis Leftakis, who ran a taverna, stating it 'just happened' as she was feeling 'low', despite still loving Mr Slotsaa. Upon meeting Mr Slotsaa at the airport after spending the night with Mr Leftakis, Ms Cierpka said she started to feel better, describing it as a feeling of being wanted. She felt guilty but also that they were growing apart and he was choosing to spend time in London. She did not tell Mr Slotsaa about her fling with Mr Leftakis, stating, 'I loved Henrik. I didn’t want to break this relationship.'

Trial continues

The trial at the Old Bailey is ongoing.