Caulfield and Trent Edward Dyhrberg, both 36, and Kalabe John Steven Saurine, 22, are on trial in Brisbane Supreme Court accused of murdering Michael Zanco north of Brisbane in March 2020.
The Crown alleges Caulfield was standing less than a metre away from Mr Zanco when he fired a shot minutes after arriving at a shed on a rural property at Amamoor near Gympie.
Saurine later told police he, Caulfield and Dyhrberg had planned to steal drugs and or money from Andrew Donney but the alleged drug dealer was not at the property, the court has heard.
Prosecutor Michael Lehane has argued that when Caulfield pulled the trigger, hitting Mr Zanco, 22, in the head, he intended to kill or cause him grievous bodily harm.
"Or if he didn't have that intent he was part of an unlawful plan to rob and or assault which involved the use of weapons including the gun."
Saurine and Dyhrberg should bear criminal responsibility as they were part of the plan, on the Crown's version.
"We're not dealing with an "Ocean's 11" scenario ... there's no George Clooney, no planning over months; it was primitive in the extreme," Mr Lehane said about the plan.
But defence barristers told jurors on Wednesday there was no common plan involving Dyhrberg and Saurine to use a firearm.
Mr Zanco died the day after the shooting after Caulfield took him to hospital in the back of his ute before fleeing.
A person who rushes a critically injured man to hospital is unlikely to be someone who intended to end his life, Caulfield's barrister Patrick Wilson said on Wednesday.
Hospital footage showing a distressed Caulfield was fundamentally inconsistent with the Crown's case against his client, Mr Wilson argued.
The men's lack of disguise suggested there was not even a simple plan and there was a lack of admissible evidence about what happened in the shed, he told jurors.
Justice Peter Davis will sum up the case on Thursday before the jury retires to deliberate.
