A fourth defendant, Lisa-Marie Smith, 26, of Hawick, Roxburghshire, was unanimously cleared of murder and an alternative charge of manslaughter.
Jailing Sebastian Smith, Palmer and West-Davidson for life Judge Levett directed that Smith should serve a minimum term of 21 years before he can be considered eligible for parole, Palmer for 18 years and West-Davidson for 17 years.
Sebastian Smith refused to leave prison to come to court and was sentenced in his absence.
In a letter read to the court he described the trial process as being biased and said he didn’t see the point of coming to court.
A policeman guarding the scene in August 2018.
Joe Pooley Ipswich murder sentencing: Mum addresses killers
ipswichstar.co.uk - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from ipswichstar.co.uk Daily Mail and Mail on Sunday newspapers.
Reserve at Lake Butler Sound estate tops Windermere-area sales from April 24 to 30 | West Orange Times & Observer
orangeobserver.com - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from orangeobserver.com Daily Mail and Mail on Sunday newspapers.