Other mistake: When Chris and Snoop go to kill Bug's dad, they have their high powered nail gun once again, even after previously throwing it in the marsh with the guns. Bought a new one? Not likely as the reason for throwing it away in the first place was because the cop saw it. Buying an identical one would defeat the purpose of ditching it.
Audio problem: When Carcetti is talking to the Interdenominational Ministerial Alliance, there is a moment of silence after he announces that he'll treat them fairly regardless of endorsement. During this moment of silence, the shot changes to an angle where Carcetti is mid-speech, while the audio is silent. The scene resumes in sync with the audio as soon as the shot changes.