Sebastian Kalinowski: Mother and partner guilty of murdering teenage son

Sebastian Kalinowski, 15, came from Poland to stay with his mother in October 2020

A mother and her partner have been found guilty of the murder of her 15-year-old son.

Agnieszka Kalinowska, 35, and Andrzej Latoszewski, 38, tortured Sebastian Kalinowski for months before he died in Huddersfield in August.

Sebastian was beaten with a bed slat, whipped with an extension cable and stabbed with a needle, jurors heard.

The couple had denied murder but were found guilty after a six-week trial at Leeds Crown Court.

Sebastian died in hospital on 13 August of an infection caused by "untreated complications of multiple rib fractures", after weeks of what prosecutors described as "cruel assaults and abuse".

Agnieszka Kalinowska and Andrzej Latoszewski are due to be sentenced in October

The teenager arrived in the UK from Poland in October 2020 to live with his mother and her long-term partner, the court heard.

However, the arrangement quickly turned sour, with one family friend telling jurors they believed the couple came to view him as a "hindrance".

Over the following months Sebastian was repeatedly beaten by the couple and subjected to cruel and humiliating punishments.

In text messages between the partners, they described their own actions as "torture".

Stabbed in groin

Footage from a CCTV system installed by Latoszewski to spy on Sebastian captured the abuse.

In one 30-minute clip played to the jury he could be seen hitting the boy more than 100 times, pausing at one stage to wipe the sweat from his face, while Kalinowska watched TV and ate toast.

On the day before Sebastian's death, Latoszewski was seen on CCTV forcing food and drink into the boy's mouth and stabbing him with a needle in the groin and thigh.

Prosecutors said he was "apparently laughing whilst he did so" before Kalinowska took over stabbing her son.

• How killer couple were caught by their own CCTV

Agnieszka Kalinowska and Andrzej Latoszewski were convicted after a trial at Leeds Crown Court

Sebastian was also verbally abused by the couple and ordered to address Latozsewski as Mr or Sir.

On the day the boy died Latoszewski waited more than two hours after finding him unconscious before calling for an ambulance. He later claimed Sebastian had drowned in the bath and that his injuries had been the result of a fall from a tree or a fight.

The jury took just three hours and 39 minutes before returning unanimous verdicts against both defendants.

After the verdicts were delivered Kalinowska began crying in the dock.

Daniel Lee from the Crown Prosecution Service said it was "impossible to contemplate the agony and fear this young boy experienced, inflicted in his own home, by his supposed care-givers".

Sebastian was due to start his final year at school when he was killed

Adjourning sentencing until October at the earliest, Mrs Justice Lambert paid tribute to the jury's "truly extraordinary" dedication.

She told them: "You have had to endure quite horrifying footage of Sebastian suffering great pain over a long period of time and then his death.

"You have gone beyond the call of duty. Therefore, I take this step of discharging you from all jury service in the future."

Det Ch Insp Tony Nicholson, who led the investigation, said the jury had sat through "very harrowing evidence in what has been a lengthy and difficult court process".

"Detectives and partners in the CPS firmly believe that the charge of murder truly reflected the physical abuse Latoszewski and Kalinowska inflicted on Sebastian, and we are pleased they have been found guilty of this offence," he said.

"We await their sentencing and our thoughts are with Sebastian's relatives in Poland."

Sebastian's headteacher Andrew Fell, of North Huddersfield Trust School (NHTS), said the teenager would "be remembered for his charming smile, his sharp sense of humour and his kindness".

He said: "Sebastian was happy at NHTS.

"His spoken English improved significantly, helping him blossom from an initially shy student into one with much more confidence and a strong circle of friends."

'Campaign of abuse'

Tracy Brabin, mayor of West Yorkshire, welcomed the verdict and said it was a "deeply upsetting and truly shocking" case of abuse.

"I will never understand how someone could treat any child, let alone their own, with such abhorrent cruelty and contempt," she added.

Helen Westerman, from the NSPCC, said Sebastian's mother and her partner were the "very people who should have been nurturing him".

"People will be asking how any child in our society could suffer such an appalling campaign of abuse without anyone intervening.

"That is why it is so important that no stone is left unturned in the review looking into the circumstances around his death," she said.

A spokesperson for Kirklees Safeguarding Children Partnership said a review of the case had been commissioned, adding that "the outcome will be published in as timely a manner as possible".

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