Factual error: Some Freightliner M2 trucks are shown in 1990. That did not come out until 2002. (01:32:56 - 01:35:20)
Factual error: There is a "Covered California" sign in a window. The referenced health insurance exchange did not exist during the 1990 time setting of the movie. (00:20:58)
Continuity mistake: In the desert digging, the Nova's trunk is open, then shut. (01:42:00 - 01:45:00)
Revealing mistake: Deacon uses "hidden" food to get the dog to come up to him. The "treat" is largely concealed - but the dog's slobber gives it away. The camera shifts after Deacon's hand goes next to the dog's mouth, giving the impression that Deacon is just petting the dog under his neck. (00:06:35)
Suggested correction: He was feeding him. You can see him eating out of his hand. The food isn't "hidden" You can hear the dog sounding as if he were eating something and his face is in his hand. Those were added sound effects in post. At first glance I got the impression he was giving the dog a treat as they were pals.
Part 1: Based on the circumstances plus Deacon's actions immediately before, during, and after his encounter with the dog, I believe it was a lousy attempt at luring the dog but trying to give the impression there was no lure (food). Deacon did not have food when he came out of his house and wasn't expecting the dog to be there. Deacon even pointed his right fingers toward the dog when he said, " You [are] the one [who has] been gone for the last two weeks." Deacon stoops down and [continued].
Part 2:...makes an effort to point his right hand fingers downward, again giving the impression he wasn't holding anything (food). If feeding a hungry, cautious dog, I think he would have displayed the food in the palm of his hand (what is there to hide if actually feeding the dog?). When "sneaking" the food into the dog's mouth, a small piece can be seen falling to the ground. Deacon holds the dog under his neck, probably to keep the dog from reaching the food that has fallen.
Part 3: (The dog later picks up the piece that fell.) Taking all these odd movements into consideration, I'm sticking with my assertion - Deacon "surreptiously" lured the dog, but his actions were noticeable, thereby revealing what was actually happening. Also, if the dog was missing for two weeks, Deacon would not have been likely to bring food out for the dog that morning. Anyone wanting to view the scene and serve as a tie-breaker, start at 00:06:26, watch Deacon's right fingers @ 0:06:32+.
Deliberate mistake: Denzel Washington never wears a vest (at least during the previews). All deputies are mandated to wear at least a level II vest (most will buy a higher protection vest) whenever performing Sheriff duties. Plus his duty shirt is just plain sloppy looking, way too big for him.
Continuity mistake: When Sparma turns the envelope upside down to empty it, he throws it on the desk, and it lands face up. When the shot changes, the envelope is facing downwards.
Continuity mistake: When Sparma drops the photos inside the envelope, the way they fall on the desk differs between the first and second shot.
Continuity mistake: During the interrogation, Baxter hands Sparma a card, which he picks with both hands, then puts his left hand on the table. A shot later, his hand is holding the card again.
Continuity mistake: During the interrogation, when Baxter asks Sparma why he abandoned his car, Sparma's left hand is either bent next to his face or lowered.
Continuity mistake: Baxter hands Sparma a photo, which lands next to the mic on the desk. The mic is either a few inches away from Sparma or right next to his hand. Also, Sparma's hand is either on the table or not, depending on the shot.
Continuity mistake: When Sparma holds the girl's photo, the position of his hands is not continuous between shots.
Continuity mistake: When Deke is about to step into the interrogation room, Sparma's hands are crossed over his belly. Then, half a second later, his left hand is on the desk, covering the picture.
Continuity mistake: The number of garbage bags containing Sparma's possessions vary when being transported in Deacon's SUV. Initially, only a few are visible in the cargo area, then a view shows many more, followed by fewer as Deacon continues to drive. When Deacon got to the site, it didn't look like there were any bags in the cargo area, but he POSSIBLY could have already got rid of them; this wouldn't make sense because there were many holes already dug at the site. (01:51:23)