Plot hole: Delores is walking into the murder scene at the beginning of the movie just as Ernie is shot. Later, while she is being questioned, she tells the two detectives what the thugs said and did, yet, she was not eavesdropping or looking through the door.
Plot hole: In the scene where the limo driver gets shot, Deloris walks in just as the bullet is fired. She doesn't see what happened before, just the guy getting shot. However, when she is telling the police what happens, she tells them that Vince looks at Ernie and says 'Good night.' He did, but she wasn't there at that point.