The easy response to this (and the other "Is adventure mode broken" thread) is simply to quote Toady's latest dev message:
It's difficult to get it right, and it's not going to be quite up to the level where it'll need to be for the justice/crime features later on, but we're trying to keep everything pointed in the right direction.
Basically, the feature you want (justice/crime) hasn't been started yet. I really doubt it will be done in the next 2.5 years, because the next thing is myth/magic. Hopefully there will be some improvement with the latest changes since it addresses information flow, but I would heed his warning: it's not going to be quite up to the level that will be needed.
Let me back up a bit, though. Consider what Toady has always said about what inspired adventure mode: the idea that there are "bones" files in rogue-likes that let you explore the actions that you previously took. Indeed, this is one of the most compelling aspects of DF overall. There is a history that you can take part in and explore.
There is one feature (turned off by default) that I have never heard anyone use: Legends mode can be configured to hide details that you have not yet discovered in adventure mode. The idea is that the history only becomes accessible once you visit places, talk to people and learn about it. With that in mind, you might be able to imagine a very different kind of adventure mode than you might have thought about before.
Instead of viewing adventure mode as a typical rogue-like where you wander around killing things indiscriminately in order to level up and become more powerful, imagine a game where combat is self defence and your goal is to discover things about the world. With this way of thinking, the prioritisation of features in the game makes a little bit more sense (to my thinking, anyway).
But, let me riff off your original theme, because while I wouldn't say adventure mode is "broken" it's only because I've never been under the impression that it ever "worked" at all. You start the game and you have absolutely no context at all. The map is unfamiliar and the recent events are difficult to discover unless you know where to look. The "quest" system is clearly a placeholder with your lord telling you that some menace has been plaguing your civilisation for years, never mind that the menace in question is on another continent and has never had any interaction with your civilisation *ever*. You hear about armies on the march, with no indication of who is involved or why they are fighting (even though that's all nicely accessible in legends mode).
You meet people and learn about them, but the only way to discover those facts is to tell stories about them. And when you do, you have access to almost everything ever known about them. You can ask about their family, but then you can't ask them about the person they just mentioned. You can look at your events page, but you can't ask anyone about the events. You can even spread rumours about these events even though you have no way of following up what's going on. You can hear about buildings in a city, but you can't ask anyone to give you directions to the building.
Basically, unless you are very, very skillful at the game, there is virtually no way to get any context about the world and any reason to do anything. So people just wander around on killing sprees, thinking that this is the point of the game. And it's strange because you meet a bandit travelling on a "mission" and you know they are a bandit. So you kill them, but you companions think you are unhinged and tell everyone they see what a maniac you are. So now, you are labelled a killer. Or you visit a bandit camp and they don't attack you, so you attack them first -- but really, what is your justification? "I know they are bandits!" And when the bandit leader screams for mercy, if you grant it -- he just goes back to being a bandit leader. In fact, if you don't freaking kill every single one of those bastards, the bandit camp just keeps operating (how strange...) And your companions think you are nuts.
But the thing is, if you go to a village and witness the bandits attacking, and if you rescue the victims and then go to the bandit camp, kill everyone and then return to the village to report your success -- you will be a hero. And if you go to the next town, who has never heard of the bandits, you will be a murderous nutcase.
I think this is the subtlety that escapes most players. The game is not about killing, it is about exploring the world and discovering the context. It's just that the tools are *so* poor that this is really, really difficult to do. The fact that you can murder a whole town and the rest of the civilisation does not willingly rush to fall on your sword is inconvenient, but when taken in the whole of missing features it seems like a drop in the bucket to me.
Which is not to say that adventure mode is not fun. It is tremendous fun. But there are just huge swaths of ground where you are going to have to look the other way and imagine that it works the way you want it to. It's just not even close to finished yet.