'Never mind all the talk,’ Moons kept the pistol on Kidd. ‘I would have found him sooner or later. This way everybody gets saved a long train ride.’

Timpey has just revealed that he was the one who leaked Kidd’s location to Moons, against Scallen’s direct orders. To that, Moons says it doesn’t matter whether or not Timpey told him where Kidd was, because the outcome would have been the same in the end. In this moment, Moons reveals a perspective that always undergirds vigilante justice: he believes he has moral justification to seek vengeance for his brother’s murder and he justifies his actions by saying that if he kills Kidd, it will ultimately be better for all concerned. This perspective is precisely what makes vigilante justice dangerous. It is the work of a determined man who believes that his interpretation of the law, rather than the interpretation of police, lawyers, judges, and jurors, is the correct one. This perspective inspires a reckless, and therefore dangerous man, and undermines a common justice system that all should be able to rely on.

‘You pull that trigger,’ Scallen said, ‘and you’ll hang for murder. ‘Like he did for killing Dick.’ 

‘A jury said he didn’t do it.’ Scallen took a step toward the big man. ‘And I’m damned if I’m going to let you pass another sentence.’ 

‘You stay put or I’ll pass sentence on you!’

Bob Moons is preparing to pull the trigger on his Colt, having forced Timpey to take him up to Room 207, and Scallen is warning him not to shoot. Moons is proving himself to be a dangerous man, not just to Kidd, but to everyone else in the room and maybe other people who are outside. This is the moment that Bob Moons is trying to take the law into his own hands, regardless of what Scallen, the marshals, and the courts have decided under the laws of the territory. He is ready to serve as judge, jury, and executioner for Jim Kidd. He is also willing to harm Scallen if he interferes. As Scallen reminds him, Moons is facing hanging for a murder charge if he kills Kidd, which is far worse than the five-year jail sentence that Kidd is facing. This moment reveals how dangerous vigilante justice can be, and why it is unacceptable in a society of law and order. If Moons tries to kill Kidd, he could set off a gunfight that could kill Scallen, perhaps Timpey, and maybe other people who are nearby.