I read the negative comments before viewing this film and undeterred, went ahead and started watching. I admit that I had to rewind quite a few times as the film is incredibly complex, involved and full of detail. That is a good thing but also, quite unexpected in this culture of car chases, explosions, gratuitous sex and general violence that substitute for plot and character development. In fact, what a welcome departure, however, I am so used to not paying a lot of attention to what I watch.
This film is chock full of character development and plot line; the kind that we used to analyze when I was in high school. It requires actual mental participation on the part of the viewer. What a nice change. I would compare it to 'All The President's Men' in terms of generic subject matter. That is, it is a mystery about intense misconduct on the part of elected officials and those with enough influence upon officials to essentially 'own' them.
Unlike 'All The President's Men', this film makes an effort to give a couple of the characters actual personality. In this sense the movie is a character study like 'The Negotiatior' with Samuel Jackson and Kevin Spacey. In that movie, their characters are both city employees and the plot is extremely intense. Yet, the plot is dependent on the ability of their characters to cooperate with each other, trust each, and ultimately unite together against the corrupt Police Department. There is more gun fire in this film and the specific plot is different but generically, there are many similarities.
I WILL say that City Hall requires a whole lot more concentration. In fact, I was struck how parallel it was to past and present political scandals I've seen in my life going back to Watergate. The thing is, the public knows that something is wrong, for sure! but following the details is hard to do. This movie is not even close to being as complex as real life but it actually is realistic to life in its complexity. I think that is one of the reasons that previous posters have criticized the film: unrealistic expectations.
If one watches this knowing what they are about to see and are up to the experience, it really is excellent! I watched it 3 times in a row! The acting is superb and the directing is flawless. The weakest link is John Cusak's accent.

I am a huge Michael Madsen fan, so needless to say, i bought this movie without even renting it or anything... This movie was so horrible, i didn't even take it back to the store, i wouldn't want anyone else to be subjected to this human poison, i just threw it in the trash, never mind the money, it was worth the price to be able to throw it away. The acting wasn't that bad, it wasn't good or anything. The story was horrible, and the ending was something i despise. He was a broken man, alcoholic. his life was a bunch of junk. i thought his horse, peanuts, was an awful device to show his childhood innocence, a dog would have been much much better. i also hate religion, so this ending without a doubt angered me. Jesus heals all... i hate that i know people just like this that are huge Christians and catholics, and time will show that god doesn't heal all, or anything. It was a horrible movie, if u have the option to see it, pass, or better yet buy it, or rent it, and throw it in the garbage, and leave the coffee grounds on it in the morning