Character mistake: When Nick and Morgan are commanding the dog to find the victim's scent (and the crime scene), they both use commands in French, e.g. venez (come), trouvez (find), allez (go), and restez (stay) - these are all formal versions of each verb. Why would they command in a formal manner?
Suggested correction: Because that's the manner in which the French train their dogs - they are ordering them to do something, not asking them.
Corrected entry: Many of the dead bodies in a crime scene, or cadavers during an autopsy in varied episodes are breathing.
Correction: This one is going to have to be more specific about which dead body and when as most of the time a dead body was used for the series (especially in autopsies and when they found the bodies initially); it was a prop based on a real person and thus could not be breathing as it never had life to begin with. Exceptions were when it showed a person actively dying on screen where them breathing may have been a last breath. This is going to need to be more specific to verify as a definitive mistake.
Plot hole: A central plot device in this episode is that there is no six letter word made up of the letters EXVIN, so the murdered man cheats at the word game by playing a word he knew to be inadmissible - exvin, a wine connoisseur who no longer drinks. Since he is supposed to be a stone cold killer player at this word game, don't you think he would have thought of Vixen? Sara Sidle points that word out later - why wouldn't a world champion word game player have figured it out, using a safe, common word and avoiding a possible challenge?
Suggested correction: If you watch the episode (timecode 00:36:20), in the flashback it shows exactly why he did not use vixen. There were 2 spaces between the "x" and the "n" on the board, so Adam played a bluff and used the fake word exvin.
Shock Waves - S11-E1
Character mistake: When Sarah enters the lab with the bagged microchip, she tells Greg and the other CSI that she got it from Doc Robbins, when it was Super Dave who'd found it during autopsy.
Suggested correction: Sarah is standing beside Dr. Robbins when he finds the SIM card within what's left of Officer Clark's chest cavity, during autopsy (timecode 00:19:35). Dave wasn't even near Clark, he was with the corpses of Officers Morales and Hooper.
Factual error: The CSI doesn't prioritize cases by importance, and have samples from big cases go first like they do on the show. They don't have the lab in house like on the show. It's too expensive. They have to send samples from even the most important cases, to labs where it takes weeks to months to test DNA to keep down costs. They also have to do this to make sure DNA testing is done correctly. DNA has to be tested multiple times because mistakes can be made.
Suggested correction: This entry is half correct and half incorrect. It is true that DNA is not as accurate as the show depicts and no lab would run it one time. However, some CSIs do have a lab "in house" as in some units that's their "office" so to speak. Not true of all of them, but is for some. While law enforcement won't openly admit this; they do put a rush sometimes on high profile cases as they have a reputation to maintain and it won't look good to the public if results aren't coming back quick enough.
Cool Change - S1-E2
Plot hole: Grissom examines the victim's body and immediately rules it a homicide because he was wearing eyeglasses. He states that suicide is a cowardly act and no coward wants to see their death and would have removed their glasses before committing suicide. What a completely unfounded, and unscientific, statement. Suicide being an act of cowardice is his opinion and not a scientific fact and they don't work off opinions: they always state how they work off the evidence.
Suggested correction: This is correct, that was not scientific on Grissom's part, however this wouldn't be the last time Grissom formed an unscientific opinion that he was sure of based off what he thinks to he true as have the rest of the CSIs in several cases throughout the series. This also happens in real life; people involved in crime scenes making assumptions thus making errors off it. It wasn't right; but I would hardly call this a plot hole as this is something Grissom legitimately believes.
Other mistake: In the flashback that shows Adam Brenner playing his opponent using the word "Exvin", we can see that the X is also used in "Juxtapose". When the opponent adds an S to "Exvin", he is challenged and made to take back his tiles. However, the X would remain where it is because it is a part of another word. Since the opponent plays a word using an X later in the game ("Loxodrome"), we know that he must have taken back the X as well. However, that cannot be the case as then "Juxtapose" would not be able to stand without the X. He couldn't play it as part of "Exvin" due to the existence of the word Antothenics underneath Juxtapose.
Suggested correction: I think they were implying that he played a second ex and that's what prompted them to look to see which tiles were missing from the suspects game. Since there were two x's used in the game and there's only X in each set it implies they thought someone was bringing tiles in from another set, and then they looked at the suspect set to see if any tiles were missing.
Corrected entry: Jayse, the reindeer owner, states that reindeer are indigenous only to Iceland. Dead wrong, reindeer also exist in northern north America and Canada, as well as in northern Europe and northern Asia. (00:10:00)
Correction: That's not what he says, nor means. He said the snow reminds the reindeer of Iceland, "the only place you can find real reindeer." But this would be like a New Yorker saying "New York is the only place you can get real pizza." He simply feels Icelandic reindeer are the real thing and everything else is a subspecies of Caribou.
Other mistake: Despite the city-wide outage from the storm, there's quite a visible glow around the house as Sarah and Nick investigate the grounds, that isn't moonlight.
Suggested correction: A personal generator? Or (more likely) a generator from the CSI gear?
Continuity mistake: In the opening scene, the female student is wearing green panties. When the two bodies are found, she is wearing red panties. It was a murder behind a locked door, so no one changed them for her.
Suggested correction: The girl had green panties with pink or red strings. When she was found, all that was visible was the string.
