In the pilot, Greg Morris' character is Lt. George Nelson but in the series he becomes Lt. Dave Nelson.
In exteriors of Dan breaking into pimp's apartment, he is in full view of parking lot; but in reverse shots from apartment interior there is another building wing directly behind him.
Bloody Mary mysteriously materializes on cocktail table midway through Dan's discussion with parents of missing girl.
When Red Buttons is observed to possibly be scamming the slot machines, it would be the responsibility of the casino's security team to confront him, not private eye Dan Tanna. Casinos have cameras watching gamblers every move. A security official does show up near the end, however.