Broken Aesop: An example relating to degree of openness. Cases 2-4 and 3-5 are all about bringing The Truth to light, especially when Edgeworth is involved. The issue is that the view of when the truth should be brought to light expressed through the events of the game is a nuanced one, while the view expressed through the dialogue is an absolute one. Edgeworth's dialogue after his Heel Face Turn could be summarized as "expose the truth, no matter how painful." Yet there are situations in which players are supposed to hate someone for exposing the truth.
Situations where revealing the truth is praised:
Telling a man who already knows that he was deceived by his girlfriend five years ago exactly how he was deceived? Sure, the truth turned out to be that he hadn't been as bad a judge of character as he thought he was, but Edgeworth starts pushing for the Truth to come out without knowing what it is. Edgeworth inherently knows that The Truth will heal the man's pain even if it gives him more to be upset about.
Situations in which revealing the truth is condemned:
Telling a jealous man the truth about his fiance's ex in order to make him reconsider the marriage? How evil! (The timing of the reveal is implied to have been part of what made it evil, but the heroes don't exactly tread lightly when it comes to the timing of big reveals either.)
Telling a skeptical public about a very unconventional technique the police used to solve a case, that lead them astray? Or publicizing a politician's affair with a secretary? The work of an evil man who caused nothing but pain. (The truth was definitely not the culprit's motive, but revealing the truth about what the police did was an effect nevertheless.)
Situations in which exposing the truth was portrayed in a mixed light:
In Ace Attorney Investigations, it is clear that the Yatagarasu's tendency to "steal evidence of corrupt dealings of all kinds" and send it to the press is illegal and that Edgeworth would like to be above such actions, but the Yatagarasu's actions in this regard are hardly portrayed as evil. The Yatagarasu was just "stealing the Truth" in order to bring it to light.
At one point, Edgeworth threatens to publicize a witness' embarrassing psychological diagnosis unless that witness testifies truthfully. He says that it's not his problem if the witness chooses to commit suicide in response to the psychological profile being publicized.
A case could be made that revealing the truth really was good in the situations where it was portrayed as good and bad in the situations in which it was portrayed as bad, but the dialogue describes bringing The Truth to light as though it is a golden ideal that is always good - as long as the person doing it is a good guy, and the person whose truth got exposed only considers committing suicide rather than actually doing so.
Complete Monster: Unsurprisingly for a murder mystery series, there are a lot of horrible people. Among the series' most vile villains are Manfred von Karma from the first game, Matt Engarde from Justice For All, Dahlia Hawthorne from Trials and Tribulations, Kristoph Gavin from Apollo Justice, Quercus Alba from Investigations, Blaise Debeste from Investigations 2, and the fake Bobby Fulbright/The Phantom from Dual Destinies. Redd White, Morgan Fey, and Calisto Yew are also pretty bad as well.
And Larry Butz. Seriously, with how his role is in the games its as if the developers practically knew he would be popular.
That, or they like hearing a collective moan from time to time.
EMA SKYE! Seriously, she could have easily been a Replacement Scrappy, but is instead one of the most loved characters of the series. Not only that, she replaced fan favourite Maya for a case and Gumshoe for an entire freakin' game, and was popular enough to be the original protagonist of what eventually became Investigations.
Fridge Horror: The games become a lot less fun when you realize that Japan's court system is pretty much exactly like how it is presented in the games; not to mention that Phoenix and co. would be social pariahs for being defense attorneys.
Het Is Ew: Any time a female character gets involved with Phoenix or Edgeworth, prepare to see a shitstorm amongst Phoenix/Edgeworth shippers.
Ho Yay: Phoenix Wright and The Rival Miles Edgeworth certainly have some rather... intense... feelings about each other. On the flip side, there's Mia and Lana's "intellectual attraction" and the various weirdness surrounding Adrian Andrews and her co-dependency. The fourth game seems to toy with this more than most with Apollo and Klavier. For example, upon meeting Apollo, Klavier says, "I must say I'm used to being inspected by the ladies... But this is the first time I've felt this way with a man." Capcom is definitely aware of the implications, and love to be as vague about it as possible.
Also, some of the concept art for Investigations, especially the one of Edgeworth and Gumshoe sharing an umbrella.
Edgeworth and Shi-Long Lang on Investigations. The later have a penchant on calling Edgeworth a pretty boy and getting on his personal space since the beginning, not to mention the banter between the two have certain... tension.
Well, there is this pic as well. Some fans have joked that it would have been more blatant in a good way if Maya wasn't in that picture. (But of course whether if Maya's presence make the pic even better or worse is of course up to you.)
Iron Woobie: Pretty much all of the sidekicks in their own way, most notably Maya. All chirpy and active, but each of them lose their parents at a young age, and have to deal with various other amounts of angst.
Magnificent Bastard: Manfred von Karma and Damon Gant in the first game, Matt Engarde in the second game, Dahlia Hawthorne in the third, Kristoph Gavin in the fourth and Quercus Alba in Investigations. In short, all the big bads from each game!
Most Annoying Sound: Winston Payne's wimpy-and-girly-sounding Objections whenever he appears will make you want to grab Franziska's whip and whip the arrogant fool into submission.
Franziska's whip, whenever it's hitting the player character.
Mike Meekins' megaphone feedback. WEEEEEEEEEN!
The explosion that comes with your Life Meter going down.
Nightmare Fuel: Investigations may have finally succeeded in communicating the Badger's creepiness to the audience. Then it sneaks up on Edgeworth with a sword in a haunted house and Jesus Christ that thing is made of nightmares.
One-Scene Wonder: Ema's appearance in Ace Attorney Investigations was hyped up quite a bit in promotional materials, and there are rumors that the game was originally planned to star her as the player character. In the end, we get about five minutes of actual dialogue from her in a brief and somewhat tacked-on cameo that was more or less just there to establish an investigation technique that never appeared again. She does have a larger role in the sequel, however.
The Scrappy: Marvin Grossberg, in the third game. Not so bad in the first, but in the third, he just will not shut up about his hemorrhoids.
That One Level: Many consider Moe's cross-examination to be a real pain in the ass, since one wrong press will get you penalized, and culminates with his last testimony, in which any pressing will cause you to instantly lose.
Values Dissonance: Several cases are built upon expensive medical bills. In countries where healthcare is free at the point of service this seems very strange.
In one case Shi-Long mentions that guns are 'very hard to obtain in this country' and uses this as evidence to accuse a policeman. In the localization the game is set in Los Angeles, where this is very untrue.
And then of course, there's the entire court system which is a satirization of the Japanese court system which itself looks alien and unjust to Americans familiar with the adversarial system and with the deeply enshrined principle of "innocent until proven guilty."
What Do You Mean Its Not Symbolic: Furio Tigre's shirt has a picture of a tiger biting the head of a dragon—Phoenix's Japanese given name has the kanji for dragon in it.
The Woobie: Adrian Andrews, Miles Edgeworth, Vera Misham, Trucy Wright, Iris, Pearl Fey, Maya Fey... the list goes on. Some characters who aren't even The Woobie get woobie moments.