DS Swain led the police investigation into the assaults on Nina Lucas and Seb Franklin which led to the latter's death in May 2021. The two were attacked by a gang led by Corey Brent and comprising of Kelly Neelan, Eli Higginson and Jason Dowling who took a dislike to Nina's Goth appearance.
With forensics covering the crime scene, and while Nina and Seb were being given emergency treatment in Weatherfield General, DS Swain spoke with Abi Franklin in the waiting room. She got off to a bad start with Seb's mother when she tried to establish possible motives for the attack and asked if the two victims were drug users. As a former addict herself, Abi reacted badly to what she was as victim blaming based on her own past record and didn't believe Swain's assurance that the only reason for the question was that the attack had taken place in an area known for its drug use.
When Nina recovered consciousness after her operation, Swain questioned her as she lay in her hospital bed. The tearful girl was able to remember few of the events leading up to attack when she saw Corey and his friends when they first encountered them at the Aquaside Industrial Park, only recalling that someone had slapped her across the face and that Corey and Kelly had been there at the time. As a result of this information, DC Wiley arrested Kelly while Swain went to see Corey at his flat at 12 Victoria Court. He had pressured his girlfriend Asha Alahan to lie and provide a false alibi for him but when it came to the crunch, she was unable to comply and told Swain that she was unable to verify that he had been in the flat at the specified time of 8.30pm. She therefore arrested him and took him in for questioning.
Corey's father, Stefan, sat in on the interview having first advised his son to admit nothing. To Swain's frustration, Corey's initial answers were all "no comment" when she tried to ascertain his whereabouts on the night of the crime. Eventually the boy gave way and admitted to being in the vicinity but not to being part of the assault. Further evidence emerged when Abi listened to a final phone message that Seb had sent her, just before the assault began which included the sound of a girl laughing. Swain brought Kelly back in and told her of further forensic evidence that both placed her at the scene and as part of the assault, including the slap to Nina's face. She tried to convince Swain that Corey was the key player in the attack and that she had been horrified by what was happening, but the officer then presented her with the phone call and the information that Corey had made a voluntary statement to the effect that Kelly was the perpetrator, something that was backed up by forensics as Corey had been careful to clean up his own clothing afterwards.
As Nina convalesced, she recovered some of her memory and was able to give a fuller statement to Swain but she was horrified to hear that Corey had been released as there was not enough evidence against him. Asha was determined to change that state of affairs and, using a supply obtained by Abi, drugged Corey's drink in the hope that in his high state, he would incriminate himself. Whilst that didn't happen, Asha was able to use his unconscious facial recognition to open his new phone and saw on a tracking app that Corey returned to near the scene of the crime at 3.07am a couple of days after the attack, followed by a walk to the River Irwell. Asha and Abi handed over the phone to DS Swain, withholding the information as to how they obtained the data. Following his drugging, Corey had fallen down the stairs at Victoria Court and was in the General with his father where Swain questioned him again. In the meantime, she had obtained two sets of CCTV footage that showed Corey in the same area on the night of the attack, with a rucksack and in a tracksuit beforehand, and without the rucksack and wearing jeans after. Then, two days later, he returned to the same point and retrieved the rucksack, heading then for the Irwell. She put these points to him, asking if he threw the bag into the river which was even now being dredged. Corey broke down and admitted he got rid of the items in case there was blood on them but insisted he was the one trying to help Seb. He was duly charged with GBH and murder.
She was a key witness at the trial of both Corey and Kelly in September where she gave evidence that the forensics indicated that both youngsters were at the scene of the crime though they were still unable to find Corey's rucksack. When cross-examined by Kelly's defence barrister Imran Habeeb, she had to admit that they had no proof that the sound of a laughing girl on Seb's final message was that of Kelly, though they had other ample proof that she was at the scene of the crime.
Two months after the trial, in which Corey was acquitted and Kelly convicted, Corey's clothing was discovered and handed into the police by Nina and Asha. Though Swain advised caution as forensics examined the clothes, enough evidence was found to convince them to reopen the case and re-arrest Corey. They found that he had fled with his father before this could happen, but they were eventually caught trying to flee the country after their getaway van was brought to the police station by Gary Windass. Swain interrogated Corey, revealing the amount of evidence on his clothes suggesting he had kicked Seb to death. She also revealed that in light of the new evidence Eli, who gave false testimony exonerating Corey during the trial, had admitted to being coerced into lying. Off the record, she revealed to Abi and Nina that Corey had been charged with Seb's murder.
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