The cocaine bag that Detective Curtis removes from the toilet tank would be wet and dripping. As he rejoins Detective Briscoe and the suspect in the living room, the bag is bone-dry.
When Detective Curtis discovers the bag of white powder in the toilet tank that he believes to be cocaine, he dips in a finger and tastes the substance, No police officer, especially an experienced NYPD detective, would ever taste an unknown powder. Tasting it proves nothing, and the bag could be filled with poisonous chemicals as well as any potential drug.
Canadian Consulate representative clearly says "expedition" treaty instead of "extradition" treaty.
Rey Curtis (Benjamin Bratt ) mistakenly calls a witness "Mr. Wexler" instead of "Mr. Wexman" which is what the title card before the scene states that character's name should be. Even Lenny Briscoe (Jerry Orbach ) notices this and looks at him; however the scene continues as is.