Snap Decision is notable because after 11 seasons of being filmed in B&W CBS finally decides it's time for Dodge to go color. 1966 marks the final conversion to color for most, if not all, of television. Many programs had made the switch the previous year.
In Snap Decision, Matt is in the mountains where he is preparing to take a prisoner back to Dodge. The prisoner, Gilcher, whom Matt considers something of a friend, fires his gun in Matt's direction. Matt fires back, fatally wounding Gilcher. Before Gilcher dies, Matt realizes that Gilcher was firing not at Matt, but at another man hiding in the rocks. Guilt-stricken, Matt resigns as marshal, to the shock of the town. However, when his replacement (played by Claude Akins) arrives, Matt doesn't like the way he runs things, particularly his closeness to an unscrupulous bounty hunter. This relationship might lead the viewer to think that the new marshal is a villain, but as it turns out he merely lacks Matt's aversion to bounty hunters, considering them an evil necessity. Matt also meets a polite young man claiming to be Gilcher's son, who expresses no animosity to Matt for killing Gilcher. But when Gilcher's "son" forges an alliance with the bounty hunter, Matt suspects something is amyss, keeping him from enjoying his retirement. Could they have anything to do with what happened up in the rocks? It might have been better if the exposure of Gilcher's "son" as an imposter had been delayed until the climax, but otherwise this is one of the better of the color episodes, which on the whole were inferior to those filmed during the B&W years, and which is why season 12, which began with this episode, was very nearly the last.