Something I realised recently is that almost every defense lawyer and prosecutor in Ace Attorney has some kind of neckwear.
Phoenix, Apollo, Athena, Grossberg, Godot, Yew, Eddie, Gregory, Blackquill, the Paynes, Neil Marshall, and possibly Robert Hammond (I don't remember if there's a full picture of him though) wear ties.
Edgeworth and the Von Karmas wear those cravats/jabots. The two Van Zieks brothers and Barok's apprentice also wear jabots.
Mia, Lana, and Byrne Faraday wear scarves (Mia also wears a Magatama necklace).
Aristotle Means wears a bow tie.
Kristoph wears a sort of bow.
Klavier wears a necklace with the Gavinners logo.
Jaques Portsman wears a medal.
Nahyuta wears a bead necklace.
Dhurke wears his Khura'inese Attorney's badge.
Ga'ran wears that necklace made of multiple Magatamas.
The only ones who don't are Ryunosuke (unless you count the pins on his collar), Auchi, Eustace (because he wears a school uniform that doesn't seem to include ties of any kind), and Excelsius (I don't remember if he was shown wearing anything in that one sprite of him after his fake beard was burned off but I don't think he was).
And also Kazuma was the same as Ryunosuke at first.