And today they were both sentenced to life in prison, with McLeod told he will spend at least 21 years in jail while Howarth was handed a minimum tariff of 20 years by Judge Andrew Smith.
Preston crown court had earlier heard how Howarth and McLeod paid two men, Carlton Alveranga, 20, and Richard Austin, 19, to kill 27-year-old David Totton at the Brass Handles pub on Edgehill Close on the afternoon of March 12th.
The two hitmen entered the pub and opened fire, although it is believed that the gun carried by Alveranga misfired, allowing Totton and another man to overpower them during the melee that followed.
Aaron Travers, 27, suffered gunshot wounds to the chest and Totton was hit in the face and chest, although both survived.
Alveranga and Austin fled but both later died from injuries to the chest after collapsing outside.
Detective Superintendent Andy Tattersall, who led the investigation for Greater Manchester police (GMP), said: "This was a premeditated attempt at cold-blooded murder in a pub packed with families and children on a Sunday afternoon.
"Howarth and McLeod may not have physically pointed a gun at Totton but their involvement was so integral to the organisation of this venture that without them it would not have been possible.
"But their plan was to go disastrously wrong with two young men being shot dead with one of the weapons that they themselves had taken into the pub."
He added: "Today's lengthy sentences send out a real warning to anyone considering being involved in a life of criminality or firearms."
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