Deliberate mistake: In the episode "Bunk," a man goes in the house looking for his cat. When the cat releases the fumes, it jumps down, but when the man dies, the cat is nowhere to be found. The cat is not mentioned ever again in the episode either.
Deliberate mistake: Because the series changed networks after the end of season one, this episode completely ignores that season's cliffhanger about Harm being arrested as a suspect in the murder of Lt. Schonke.
Deliberate mistake: *SPOILER ALERT* Behind T-Bag is the actor who plays Lechero, and Lechero had just died in the episode. The person was not Lechero, but maybe they didn't have another extra at hand to replace him. 'Time 1' and 'Time 2' are taken from Netflix at the time this was posted. (00:29:46 - 00:30:25)
Deliberate mistake: Elliot threatens Olivia about her testing positive for Oxycontin because she drank a peppermint mocha he brought her. If she tests positive she loses custody of her child. The thing with Oxy is that it's in one's system for a maximum of 4 days. Could be even less if only a small amount was taken and somebody exercises and drinks lots of water. Somebody could also eat poppyseeds and that would give a false positive. She could say she ate a poppyseed bagel. (00:14:00 - 00:16:00)
Deliberate mistake: The day of his scheduled departure, Poirot overhears conversations (mainly the one from the window of his room) he couldn't possibly be hearing given the long distance outdoors and the tone of voice. His reactions are shown as if he could hear and not simply see and infer the meaning. (00:23:00)
Deliberate mistake: Though the series title is technically inaccurate, since in New York CSIs are called CSUs (crime scene units), it's called "CSI: NY" to tie it in as existing in the same universe as its sister series "CSI: Crime Scene Investigation" and "CSI: Miami."
Winning Through Intimidation - S1-E15
Deliberate mistake: In the actual card game, attacking the castle ring would not be allowed, but this is probably done in order to enhance the show for kids.
Deliberate mistake: When filming the fake movie with Sophie playing the nun, many holes are made in the door, but when she slowly kneels to the ground, there isn't a hole behind her, so it seems like she's been miraculously saved. But as the scene continues, the nun starts to bleed and dies. Technically, they couldn't safely put a squib that close to her. (00:21:15)
Deliberate mistake: When the sewer worker is trying to escape the Lizard, the fast lanes in both directions of traffic are visibly clear for several blocks, which is extremely unlikely in downtown New York. (00:01:10)
Deliberate mistake: David is shown to have an illegal weapon in his home even though gun control is quite strict in the U.K. Sadly, this is quite a common practice by returning war veterans who feel safer with a gun in the house, as they often suffer from PTSD, as David does.
Deliberate mistake: Rick is talking to Joe in a maximum security facility through glass without a phone. It is impossible to hear through such glass. One would literally have to scream and still it would be difficult to hear. They should be on a two-way phone and those conversations are at times recorded, especially with high profile prisoners like murderers, mafiosi, terrorists. There's no way they would get away about discussing murder and revenge without an intercept. (00:14:00 - 00:15:00)
Just Let Go - S1-E4
Deliberate mistake: When Devon does an internet search for Chucky, pictures of Tiffany and Nica pop up. But they're still-shots from "Bride of Chucky" and "Cult of Chucky." It makes no sense that they'd be in an internet search - nobody could have taken those photos.
The Stadium - S1-E8
Deliberate mistake: The Korean lady's Mini-Uzi never runs out of ammunition, and she's spraying it at full-auto. A Min-Uzi's cyclic rate is 950 rounds/min. One long squeeze of the trigger and the weapon's dry. Same goes for all the other weapons like the M4 carbines being fired on full-auto, they have the infinity ammo cheat code going here.
Episode XCII - S5-E1
Deliberate mistake: Jack stops his motorbike beside a stream, and Jack's weapon strap crosses over his left shoulder when he walks over to have a drink. The problem is when we see Jack's reflection in the water, his image is not reversed; note the strap is still crossing over Jack's left shoulder. (00:07:20)
Deliberate mistake: Identical twins Beverly and Elliot have the exact same beauty mark on their faces, roughly on the smile line directly across from the right nostril. Identical twins don't share features like that.
Deliberate mistake: Whenever Dexter injects somebody with M99, they are immediately rendered unconscious. In reality, this would take several minutes.
Deliberate mistake: Amanda survives a plane crash into the ocean, hurricane winds in a life raft, then experimentation and attacks by giant microbes inside the alien probe. Yet when she and the others are rescued at the end, not one strand of hair is loose in her 1960s "beehive" hairdo. (00:49:05)
Head in the Clouds: Part 1 - S3-E7
Deliberate mistake: Adrian walks outside the Obelisk Blue dorm to see Chazz standing on a glass platform held up by four cables on each corner, which are attached to a helicopter flying above. Adrian then realises he is standing on a glass platform, held by cables and attached to a helicopter. There is no way he wouldn't have noticed this; he should've seen the cables, heard the helicopter and felt the glass platform beneath him when he walked onto it, even if it makes for a cool reveal. (00:12:55)
The Night of the Pelican - S4-E13
Deliberate mistake: After Jeremy Pike drops the box in front of the firing squad and it begins to emit smoke, the wind blows the smoke to the right. The actors playing the soldiers in the firing squad then move themselves into the smoke and begin coughing and choking from it.