Candy's appearance is like that of a grandmother who has aged twenty years overnight. Stress might be a contributing factor, but it's mostly thanks to Don's deliberately conservative makeover. She sports a new short haircut, oversized jam-jar glasses, and a cardigan, shuffling into the courthouse, which is swarming with journalists and curious onlookers.

It's clear from the moment we see him in Episode 5 that Don is absolutely loving this. He goes before the potential jurors and reveals, for the first time, that Candy did indeed kill Betty Gore, but only in self-defense. He promises them a hell of a story, one told by Candy herself, but he's pulling the strings, for sure. He tells Ron that the jury needs to hear that God is on Candy's side as soon as possible, and implores Pat to fix up. It's all about the optics, and Pat's sadsack cuckold routine isn't doing anyone any favors.
To be fair, not everyone is a fan of Don's showmanship either. After talking to the media and backchatting the judge, he's held in contempt and sentenced to time in county jail post-verdict, but he's still allowed to represent Candy when the trial begins, and he certainly makes the most of it.
Don's angle is obvious. When Allan takes the stand, he's questioned about the affair, Candy's friendship with Betty, the amicability of their separation, and whether he believed Candy would have any cause or motivation to kill Betty. He didn't. As far as he can tell, Candy didn't even know they owned an axe, let alone where they kept it.
Jesse Plemons is quietly brilliant here, giving only yes/no answers, but he's not much use to the prosecution. In fact, Betty's father later tells him that he might as well have been a witness for the defense.
But as far as we know, Candy had no intention of killing Betty. She didn't drive to the house to do so; we saw Betty confront her with the eventual murder weapon in snippets of flashback. This all comes up during the trial as Don asks the obvious questions of the witnesses and experts: If Candy intended to get away with it, could she possibly have been more inept about it? No. Is an axe an ideal murder weapon for a small woman? No. There were defensive wounds on Betty's body, implying a back-and-forth struggle. It seems pretty obvious that this wasn't premeditated, and likely that Betty initiated the physical confrontation.
However, there are particular problems for the defense. Well, two actually. The first is that Candy keeps taking pills which make her notably zombiefied, which the press have been keen to highlight. Don is adamant about her looking human, but Candy is adamant about her holding it together. She won't give the press the satisfaction of seeing an erratic and unstable housewife, even if they need to. The other problem is that Candy struck Betty with that axe 40 times, which makes the idea of self-defense somewhat preposterous. And the prosecution knows this; they deliberately save the pathologist until last and call him to the stand right after lunch in the hopes that one of the jurors will spill their guts and essentially end the trial then and there.
Despite the apparent contradiction, the evidence is undeniable. Forty strikes, more than what would be necessary to fell a tree, could have inflicted fatal injuries on Betty. Several of these strikes were delivered with such force that they required the axe to be wiggled back and forth to extract it, leaving deep grooves in the wood. And with only one of these wounds occurring post-mortem, it is clear that Betty endured 39 strikes while still alive. Don queries the duration of her consciousness during this ordeal, a crucial distinction as the prosecution seeks to paint a vivid picture of Betty's pain and suffering in the jury's mind. However, beyond a subtle reminder that there is no concrete evidence of the initial provocation, Don's case remains unsubstantiated. The prosecution rests its case, and now it's time for the defense to call their first witness: Candy, who is visibly struggling with her medication. When Don approaches the judge to request a delay in Candy's testimony, he's granted ten minutes - perhaps a reminder that antagonizing the judge is not always a wise move.