Police received tip-offs from as far afield as Thailand and Spain following the murder of Ashley Dale.
The 28-year-old council worker was shot dead in her own home on Leinster Road in Old Swan in the early hours of August 21 last year. James Witham, Joseph Peers, Niall Barry and Sean Zeisz were unanimously convicted of her murder following a seven-week trial at Liverpool Crown Court.
They were also found guilty of conspiracy to murder Ms Dale's boyfriend Lee Harrison and conspiracy to possess a prohibited weapon, namely a Skorpion submachine gun, and ammunition with intent to endanger life. Ian Fitzgibbon was cleared of these three charges while a sixth defendant, Kallum Radford, was acquitted of assisting an offender.
Gunman Witham was imprisoned for life with a minimum term of 43 years on Wednesday, and getaway driver Peers was told he must serve at least 41 years behind bars before he will become eligible for release. "Organisers" Barry and Zeisz were also handed life sentences with 47 and 42 year tariffs.
Detective Chief Inspector Cath Cummings – who led Merseyside Police's investigation into the shooting – has thanked members of the public who came forward with information, saying: "I'm so grateful to the witnesses who stood tall and gave their evidence at court, and I would like to thank them personally for their bravery and courage in doing the right thing. The community members who stepped up to the plate should be proud of themselves.
"They provided 332 pieces of intelligence, all of which were reviewed and acted upon. This also included 28 separate pieces of information received by the Merseyside Police major incident public portal, which was fed directly into the team.
"It's really positive to see the portal increasingly being used to provide evidential footage and information. The witness appeal regarding the vehicle seen entering Ashley’s street of Leinster Road at the time her car tyres were slashed and again at the time of her murder resulted in us being able to fast track the car we were looking for, a Hyundai i30N Performance.
"There were a total of 1,036 Hyundai i30N Performance fastback models nationally and we had to reduce that down, subsequently identifying the vehicle James Witham had been pivotal in securing just six days before Ashley's murder. Extensive forensic enquiries were conducted, 24 scenes examined and notably Ashley's home and Pilch Lane, where those charged met up before the murder.
"These scenes were held and examined for a month. It should be noted here that, with such high profile murders occurring within the space of 48 hours of each other, this was an intense period for all of Merseyside Police – notwithstanding the crime scene investigators.
"The efforts they went to meticulously gathering forensic evidence, including ballistic evidence and footwear marks and across a number of scenes, left nowhere for Witham to hide. This was second to none.
"CCTV was extensive – 48 zones were identified and footage collected from across Merseyside, Manchester and North Wales. Just short of 2,000 hours of footage was reviewed by my team and pieced together key movements of criminality across the space of a period of two months."
Police were given the names of suspects in calls from members of the public and via Crimestoppers. DCI Cummings said of the total of 333 "pieces of intelligence" received during their enquiries: "There were 28 pieces of information from members of the public, even from abroad, through the use of Merseyside Police's major incident public portal.
"Within 24 or 48 hours, we had a couple of people contact us directly. They were out of the country, but they had information.
"I think one was in Thailand, one was in Spain at the time. And that's massive, that's worldwide."
The gun used in the shooting meanwhile has never been recovered. It has not been linked to any other firearms discharges in the UK.
DCI Cummings said: "If there was any witness opportunity appeal, I would still like people to come forward with knowledge of where that Skorpion is. It's an extremely dangerous weapon."
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