Marine engineer visited prostitute after becoming 'aroused' by raping and murdering his partner, court hears

A marine engineer visited a prostitute after killing his partner as he was 'aroused' by raping and murdering her, a court heard.

Stephen Sexton, 39, strangled Joanna Derkacz, 37, a recruitment consultant, at their flat after their relationship broke down, it is alleged. 

Sexton then took her car to visit a prostitute after sending the woman a message saying 'I'll be there in 20 minutes ok baby' jurors were told. 

Prosecutors said Sexton's 'first thought after the point of death was to try and find prostitutes', adding 'it may be that the act of killing her had raised arousal.'

Sexton, a father of one, allegedly strangled Ms Derkacz using his forearm or in the crook of his elbow after subjecting her to 12 months of 'controlling and coercive' behaviour.

He then proceeded to contact two prostitutes immediately after her murder, the court heard.

Ms Derkacz was killed less than three weeks after she had warned police about his behaviour – saying he was 'very controlling' and could 'flip' at any time'.

Sexton denies murder, rape and coercive or controlling behaviour.

Ms Derkacz was found dead at their home in Waterlooville, Hampshire, on December 28, 2023.

It was heard that the pair had been sleeping in separate bedrooms for some time as their relationship had been breaking down.

Nicola Shannon KC, prosecuting, said Ms Derkacz had sent Sexton a message saying: 'Do you understand that you have been abusing me mentally and physically.

'You have cheated on me with multiple women and controlling me. I don't know what u don't understand here.

'You fucked up big time. There is no going back. You are sick by even thinking that what u saying [sic] is important. Not only that I can't trust u not only with women but I don't feel save [sic] around you.'

She then blocked his number. 

The court heard Sexton then spent most of the night at a friend's house before travelling to their flat after becoming 'pretty worked up by being blanked by Joanna.'

Ms Shannon said Ms Derkacz was in the bathroom facing the sink and had a connection to Spotify on the speaker – indicating that she was listening to music and may not have heard Sexton come in.

She said he may then have put a bag over her head before pulling her a short distance to the bed where he raped and strangled her. 

Ms Shannon KC said that there was a call made on Ms Derkacz's phone at 12.59am which went unanswered – which she suggested Sexton made to locate the phone.

She said: 'You will hear evidence which indicates that the pink phone was not opened again that night with her face ID - something which you may know from your own experience happens very easily when you pick up your phone.

'More evidence, we suggest, that Joanna Derkacz did not have use of her phone again that night and was, almost certainly, dead by then.'

Ms Shannon said Sexton went on a site called 'Portsmouth Escorts. Escort and Erotic Massage' and sent a message saying: 'Hey baby are you still working?'

The woman then sent him a postcode and he launched Apple Maps and searched for that postcode.

He then texted back saying: 'I'll be there in 20 minutes ok baby.'

The court heard he took Ms Derkacz's car and phone, as well as his two phones, with him.

Ms Shannon said: 'Stephen Sexton's first thought after the point of death was to try and find prostitutes in Portsmouth.

'Whatever had happened between them in the house it appears that the arousal that we suggest was part of the rape was not fully satisfied.

'It may be that the act of killing her had raised arousal.'

Jurors were told Ms Derkacz suffered internal fractures of bones on both sides of her neck where pressure had been applied externally. 

 The court heard the couple had been in a relationship for the last three years – one which the prosecution say had become controlling and coercive over the year before after Sexton lost his job and started taking drugs.

Prosecutors said that by December 2023 Ms Derkacz was frightened of Sexton and had told her sister he had once tried to strangle her. 

'He also took her phone more than once and broke a phone and her laptop in fits of anger,' Ms Shannon said. 

'Over the months it had involved jealousy, paranoia and attempts to control and isolate her.'

She said on one occasion he had locked her out of their home because he said she had come home 20 minutes late from an evening out with friends.

'She took shelter with one of those friends Daria. His response to not knowing where she was to report her missing to the police, no doubt hoping that they would find her for him.

'The episode backfired, however, because it acted as the trigger for her asking him to move out and for her telling the police about the breaking of her laptop and his abusive behaviour.

'He didn't move out immediately - their dogs had just had a litter of puppies and it was agreed that he could stay until they were sold, but they lived in separate bedrooms.'

On December 11, two police officers went to see Ms Derkacz as part of a 'welfare visit' and she told them that he was 'very controlling' and 'narcissistic' and 'he doesn't like it when I go out'. She added that 'he's got this thing where he flips'.

Ms Shannon said: 'Joanna herself seems to have made what we say proved, tragically, a fatal mistake, in underestimating him.

'It is one of the tragedies of this case, you may think, that although Joanna was wary, and there were, in retrospect, so many 'red flags', neither she, nor the officers, seem to have realised how far Stephen Sexton might go when he realised she was slipping from his grasp.

'Her optimism and compassion may, we say, have cost her her life.'

Sexton has a son from his previous marriage to Tara Sexton – now Ms Billington – and has a criminal record for an attack on her.

Ms Shannon said: 'You will hear evidence of Sexton having convictions for assaulting Tara Sexton and for damaging her mobile telephone. Sexton had a history of assaulting his previous partners.'

It was heard Ms Derkacz's body was found by her sister, Arleta, who was concerned because she couldn't reach her.

Arleta went to her sister's address on the way back from the airport on December 28 as she was not answering her phone – which she considered unusual.

When she arrived the door was unlocked and the dogs were running around – 'seemingly agitated'.

Sexton appeared at the top of the stairs looking 'really scared' and denied that Ms Derkacz was there as she 'went out with friends'.

Arleta said she was going upstairs to see her and pushed him away and ran upstairs where she saw her sister 'lying on the bed, lifeless. She saw her skin was grey.'

She ran downstairs and started shouting 'You killed my sister, you killed my sister.'

Ms Shannon said: 'By this time Stephen Sexton, was standing in the kitchen, holding a knife.

'When she first saw him with the knife he was staring at her. He said 'you're not leaving.'

'She said it felt like she was 'in a movie' - it felt unreal but at the same time she was petrified and froze.

'She told police that for a moment he was acting like he didn't know what to do.

'Then she saw him turn it on himself and point it into his wrist. She realised that was her opportunity to get out and she ran.'

It was heard Arleta was screaming 'like an animal' and the police were called. The nine-week trial at Winchester Crown Court continues.

Jurors have been told the case is a retrial after an earlier trial could not be concluded, and the jury were discharged.