The murder of a doorman at a Co Tyrone hotel in 1998 was compared to the killing of George Floyd in the US in a Belfast court yesterday.
Killer Francis Lanigan should serve at least 20 years for shooting dead John Knocker, the court was told.
Last month Lanigan (56) was found guilty of murdering Mr Knocker (22), who was gunned down in the car park of a hotel in Dungannon, and was handed a life sentence by Mr Justice Horner.
Yesterday his barrister said Lanigan, who fled to the Republic in the aftermath, does not accept he is guilty of the offences, and will appeal.
Following the non-jury trial at Belfast Crown Court, Mr Justice Horner found Lanigan guilty of murder and possessing a 9mm Browning pistol.
He concluded that after Mr Knocker bettered Lanigan in a fight, Lanigan armed himself with the gun then chased Mr Knocker, firing a shot at long range which brought Mr Knocker to the ground, then firing a second shot at close range.
The judge branded the murder as "an appalling act of barbarous inhumanity".
Lanigan, formerly of Knockmore Square in Lisburn, attended yesterday's hearing at Belfast Crown Court via videolink from Maghaberry prison.
Prosecuting barrister Ciaran Murphy QC said he disagreed with the defence's suggestion that this was a "low to normal starting-point case" of 12 years.
Instead, he suggested a 20-year sentence as the minimum term Lanigan should serve before being considered eligible for release.
Saying the 12-year term was "wholly rejected" by the Crown, My Murphy said: "We say this case - where a gunshot wound to the head was inflicted from a distance initially, then where the deceased was shot at point blank range through the head - is a case which falls into the category of multiple injuries. That alone would put it in the higher starting point."
The prosecuting QC continued: "Having used it to bring down the deceased to the ground, walking to him and calmly executing him by shooting him in the head is a grossly aggravating feature."
Mr Murphy said another aggravating feature was that the shooting occurred in front of bystanders.
And in a reference to the death of George Floyd in Minneapolis, the prosecutor said: "We hear recently on the news of video evidence of the killing in the United States.
"One can only imagine what a re-run of a video of this killing would look like and the horror it that would instil in anyone subjected to watching it."
Defence barrister Patrick Lyttle QC accused Mr Murphy of being "emotive and over the top" and said the defence "disagree fundamentally" with the Crown's suggestion this was a higher-point case.
Telling Mr Justice Horner that Mr Murphy was "coming in too high", Mr Lyttle addressed the Crown's comparison with Mr Floyd's killing, which was filmed.
Mr Lyttle said: "With the very greatest respect, if you witness any murder case on CCTV and see it, it will be horrifying and this would be no more or no less than any another murder case and therefore that point should be completely and utterly ignored."
Mr Justice Horner said he hoped to announce the length of the life sentence next week.