When the Judge is in the hallway, he is wearing white briefs despite the fact that he is not supposed to be wearing any underwear. In the previous scene, Foxy and Claudia removed his boxer shorts and joked about his genitalia before shoving him into the hallway, where he tries to cover up his crotch.
While Link and his girlfriend are having sex in bed, the door bell rings, and he goes to answer the door. He wraps a towel around his waist. During the fight that ensues with the bad guys, he falls back, and he is now clearly wearing underwear underneath the towel.
There are a number of scenes (stable house, car, hotel) showing Claudia wearing a green harness dress. It is quite obvious that she is not wearing a brassiere in all of those scenes. In the hotel room, where Foxy and Claudia meet the judges, Claudia removes the green dress and is now wearing a bra. It would be highly unlikely that she would be putting one on, at the same time she is getting undressed.
When Foxy and Claudia are in the hotel room with the Judge, they remove his boxer shorts. While removing his shorts, it is clear that the Judge isn't wearing any shoes, only socks. Then when the Judge is pushed and falls into the hallway, socks are visible on his feet (w/out shoes). Moments later when he is seen by the women in the hallway, he is suddenly wearing shoes and socks.
In the scene at Miss Catherine's place, there are a few stated references to it being nighttime. Yet when they go outside, it's obviously still daytime based on the visible light in the scene.
In the farmhouse, Foxy Brown siphons gasoline from a barrel outside a window into a container inside the room. The siphon couldn't work, however, because the container is at a higher elevation than the barrel.
At the beginning of the movie, Link is at a food stand with "Hot Dogs" prominently displayed on the columns. Link and the two police officers all order a Taco and coffee. When he calls Foxy on the phone, he tells her he is at a Taco Stand. The menu on the back wall does not include tacos.
Eddie moves his limbs a bit much, after Foxy shoots him in the forehead. A brain matter penetration would immediately stop the 'motor' activity.
When Jackie shoots her brother's left ear, there is a hole punched into the wall, behind him. We should be able to see into the hole, but we can't because the angle of the hole into the wallboard is wrong. From where Jackie took her shot, the bullet should be angled similarly to the (extra bright) light and the camera angle (our POV), but, instead, it goes perpendicularly into the wallboard.
Miss Katharine's line, "Four o'clock sharp at my house; you'd better not be late," was obviously dubbed in later on: Her mouth doesn't move and the sound doesn't match the rest of the dialogue.
When Foxy and Claudia are in the back seat of the limo on their way to their "appointment" with the judge, the shadow of the camera, mounted outside the car, can be seen passing over them several times as the car turns.
When Foxy confronts her brother Link, trashing his apartment while announcing that he's going "Out, Brother! Outta Town!", a hand is visible at right when she tips the television over. A production assistant's hand is shown helping to propel the television sideways. Also, studio lighting is visibly reflected in the television's screen as it topples onto the floor.