Revealing mistake: In the morgue scene where Will Smith and Martin are checking out the "fat does" for evidence, Will asks Martin to check a coffin for clues. As Martin looks through the coffin there is a shot of money that he finds inside the casket. If you look closely at this shot, the top bill in the bundle of hundreds reads "to be used for motion pictures only."
Suggested correction: May have been fixed in the DVD - I couldn't see anything untoward.
Other mistake: Marcus and Mike go into Phat Audio Video to review the video camera that they retrieved from Zoe Pounders' house. Police stations have video equipment, they could have watched it, there. For that matter, they could have watched it at Zoe Pounders' house. (00:53:25)
Suggested correction: All that doesn't contribute anything to the plot. The point is they watch the video, the rest is intentional for comedy effects. Not a plot hole at all.