When Perry is in the bar talking to one of the waitresses, he is told by another waitress that he has a phone call at the bar. When Perry starts to walk to the bar at its right end, the 1st waitress walks towards the middle of the bar (to the left of Perry). The bartender can be seen behind the bar talking to a couple with another couple to their right (between them and the phone). When the camera angle moves to the phone and sees Perry picking it up, the bartender is suddenly chatting with the second couple and the first waitress is no where to be seen.
When Stefan Riker is asked by Edward Bannister how long he has been in the country, he says 2 weeks. Yet when Perry asks Della to look up Stefan Riker in the phone book, he is listed. However, immediately after the scene when Doris goes to see Stefan, he drives up to Edward in a sports car, and Edward says: "Done all right for yourself in the past three months." Depending on when the telephone book was published, he could have been listed.
The photo in the newspaper of Doris shows her wearing a different dress and necklace than when she arrives in Perry Mason's office.