
Deliberate mistake: When Sam first meets Mickey (who is posing as a bank robber), Mickey says he needs Sam to state that he needs Mickey's help in robbing a bank, so if Sam turns out to be an undercover cop, Mickey can plead entrapment. This is a classic error. Entrapment only exists where a cop actively persuades a criminal to do something he otherwise wouldn't have done - which is not the case here. If Mickey as a con artist knows this (which is likely), it's a deliberate mistake, otherwise it's a factual error. (00:30:09)

Thank You and Good Night - S1-E8
Deliberate mistake: In the Maisels' 1954 wedding reception flashback, Midge hired professional dancers who perform the "Bottle Dance" (where they slide on their knees). This famous dance, often performed at Jewish weddings and social events, was choreographed by Jerome Robbins for "Fiddler on the Roof," which debuted on Broadway in 1964. It did not exist in 1954 but, as an inside joke, while Midge watches, she says, "That's really good. They should do something with that."

Deliberate mistake: In this episode, it is revealed Donna and Robert got together because Robert saved her from a water fountain. In "Another Bad Thanksgiving", it was shown Donna's sister introduced Robert to Donna. (00:02:20)

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: Throughout the episode, all the police station clocks are still and show the same time (3:33) in different scenes. (00:18:55)

Days of Future Past: Part 2 - S1-E12
Deliberate mistake: When the crowd is protesting outside the Capitol, the same man with black hair and a brown outfit has been drawn numerous times in the shot. (00:10:23)

Deliberate mistake: During the episode, whenever daily newspapers are shown, they lack any indication of the date.

Mercy Moment Murder Measure - S1-E7
Deliberate mistake: When Abraham throws the secret note into the fire, he crumples it up before tossing it in. But then we see a shot of the note lying open and flat on the log before burning. Not only would the note not be able to uncrumple itself, it shows no sign of being crumpled in the first place. This was obviously done deliberately so the audience could read the note one last time.

Deliberate mistake: The police force in the town is the Gendarmerie, the standard issued firearm is the Sig Sauer P2022 in 9mm. The police officers on this show carry a Beretta and not the 9x19mm one which is the model 92fs, they carry a never issued Beretta 84 chambered in .32 acp or 9mm short. Plus they use some weird holster where the gun arches out and hangs low like a cowboy holster and dangles around. Easy for a suspect to gain control of the officers gun and this happened in this episode.

Deliberate mistake: After Elizabeth goes upstairs with the pillowcases for Cindy, in the following shots there are a few long shots of Colonel Brunson's car on the road, and a couple of those shots are flipped - noticeable due to identical trees shown the opposite way. (00:03:55)

The Secret of the Unicorn: Part 1 - S1-E3
Deliberate mistake: After Francis Haddock kills Red Rackham, he lights a fuse to the explosives. The fuse that was lit is only a foot long, yet he is somehow able to climb out the ship without anyone noticing, get into a boat and swim all the way to land before it explodes. At a foot long it would have exploded in 10 - 15 seconds, all of that would taken at least 10 minutes. (00:18:45)

Deliberate mistake: Lee's old crew of three are shooting various caliber handguns at Chloe and Lee's sister. Chloe took cover behind a kitchen island. Kitchen islands are made of thin wood, the only piping in them is plastic and some brass/copper. All of those handgun calibers would have penetrated the kitchen island. (00:45:45 - 00:47:00)

Deliberate mistake: Probably best for filming the scene, but Jennifer Hart pulls up and parks her car on the street on a red curb in front of an ambulance and walks away. (00:10:12)

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: Although it was done for plot purposes, no school photographer would only take just one shot of a class photo. They generally take up to 15 to 20, as it is difficult to get everyone to look at the camera and smile at once (and hopefully not pull silly faces).

Deliberate mistake: When Thomas goes by the level crossing, a close up of Thomas is shown but it's the same footage from season 1, only flipped. Because of this, Thomas' number is mirrored.

Deliberate mistake: They show footage of Max and Larabee scouting out the entrance to a bank. This same footage was used in the earlier episode "The Treasure of C.Errol Madre".

Genesis (2) - September 13, 1956 - S1-E2
Deliberate mistake: When Sam ejects and lands on the ground, the closeup is a flipped shot, note the "US Air Force" is backwards on Sam's helmet. (00:19:10)

Plane Death - S1-E14
Deliberate mistake: When the bad guy goes to smash a table onto Michael Landon notice the plate of glass in front of him, visible. The glass is there so Landon doesn't get hurt and to make the table break into pieces in front of him.

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."