Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. Tread carefully.
When the player first takes control of Yagami, they see him posing as a homeless man, complete with a fake beard. It might not seem like much, but after how we saw Yagami's client arrested for killing his girlfriend, one could posit that this façade reflects how he sees himself: a failure of a lawyer.
Kaito's expulsion from the Matsugane Family, and the other flashbacks connected to it, are one for Higashi, Kaito's junior in the family. When a thief threatened Kaito in the family office, the latter saw that a terrified Higashi was there, unnoticed and about to attack. Instead of thrashing the thief, Kaito prioritizes Higashi's safety instead, complying with the thief and letting him have the money. Then Higashi has to watch Kaito cut his pinky off under Hamura's watch, only for Matsugane to arrive and expel him instead.
Then, in a desperate bid to bring Kaito back into the family, Higashi tracks down the thief in order to retrieve the money, only to walk into Hamura and the thief's secret deal. Compromised, Hamura shoots the thief, and forces Higashi to hold the gun as he shoots Red Nose to death. Higashi can only stand there in horror as Red Nose's body floats down the sewer waters, with Hamura drawling that Higashi "looks like a real yakuza now". Higashi's attempt to help his anikifell through, and instead landed him in serious hot water for Red Nose's murder, which he can't prove was Hamura's doing.
After Hamura reveals his position in the Kyorei Clan serial killings, the Mole comes after him shortly thereafter, fully intent on putting a few bullets in him... only for Matsugane to sacrifice himself in his place, dying right then and there. It's the one time we see the usually cold, snarky Hamura actually show emotion, and in spite of all the shit he's put Yagami and company through up to this point, it's genuinely heartbreaking to watch as he finallyrealizes the weight of his actions, pushing him to fully reveal the Mole's real identity to Yagami.
Preceding Matsugane's death and sacrifice is a short escort mission where Yagami has to protect him from the rest of the Matsugane family who have come to rescue Hamura. If any of the Matsugane family members are allowed to approach Matsugane they'll immediately hesitate to attack upon seeing their own patriarch holding his own captain at gunpoint, completely unwilling to lay a hand on Matsugane until Hamura snaps at them to rescue him.
Okubo's whole ordeal becomes this as new elements of the plot unfold. Initially he comes off as the psychotic killer that celebrated his acquittal by murdering his girlfriend and burning his house down, but as the plot roles on he's revealed to be a nasty victim of circumstance; he was initially framed for the murder that led to him and Yagami meeting, and when he was acquitted for that, the real murderer drugged Okubo, killed his girlfriend, and then framed him again. Okubo's spent three years on death row pleading that he's innocent, but no one (not even his own lawyer) believes him. The man's basically given up on living by the time Yagami returns and tells Okubo he's most definitely innocent, and while the story ends with him about to be exonerated, his future remains uncertain.
While Chief Prosecutor Morita's actions were definitely inexcusable, his family history is quite tragic. Not only did he witness his mother succumb to Alzheimer's disease, but he saw how much it had taken a toll on his older brother, who had given up his dreams of becoming a lawyer to take care of their mother, all so Morita could pursue his dream for the both of them. Then, after seven long years, Morita's brother murdered their mother before committing suicide, leaving Morita all alone. It's hard not to sympathize with Morita genuinely wanting to help in finding a cure for Alzheimer's disease, but it cannot justify him looking the other way in the face of hard evidence of human experimentation.
