Continuity mistake: When Brass and Grissom first enter the house of Ken Willard (the guy in the Polaroid), and Greg makes a noise at the door, the two of them turn around to see him. Then the angle changes, and they turn around again, repeating motion.
Continuity mistake: When Grissom, Brass, and Greg go to the house of the guy in the Polaroid, Brass picks up a credit card from a table. First, he is holding it by his middle finger and thumb from the back, then the shot changes to a close-up and he is holding it with his index finger and thumb along the sides. Then, we return to the previous angle and he is once again holding it with his middle finger and thumb from the back.
Crow's Feet - S5-E4
Plot hole: Two women die after a medical error occurs after undergoing an "anti-aging" medical procedure. A 30% solution of hydrogen peroxide is given intravenously instead of a 3% solution. According the the Material Safety Data Sheets (MSDS) a 30% solution is extremely corrosive and will blister skin on contact. 1) How did the women not bolt upright screaming as this extremely corrosive solution was pumped throughout their veins. 2) How did they not die in the clinic instead of the hours after as depicted in the show? Even in the CSI crew little experiment, the red blood cells immediately burst when exposed to the 30% solution.
Continuity mistake: As Nick and Warrick are assessing Wendy Garner's travel path and find that there are 14 minutes unaccounted for, the screen says "Wendy Jones' House". Her last name is Garner, her old last name was Clancy, and her fiancé's last name is Lanner, therefore it makes absolutely no sense to have "Jones" on the screen.
Continuity mistake: Season 5, episode 11 'Who shot Sherlock?'. In the scene where Sara Sidle sits down at the victims desk and computer, in the first shot you see the top corner of the notebook lid, saying IBM, then when you see the screen it says DELL on the bottom of it, and then in the next shot you once again see the lid with the IBM mark.
Factual error: Brown and Stokes are investigating a mysterious fatal accident involving a Jeep and a downed power line. They state that the driver would have been safe if the Jeep had made contact with the power line because the tires would have insulated the Jeep from the electrical current. Wrong. First, a car is a Faraday cage, that is an electrical current would pass on the outside of a car on the way to the ground. As long as you don't touch the outer surface, you are safe. Second, tires are (almost always now) steel belted radials and conduct electricity nicely. Lastly, it was an open top Jeep. The power line made contact with the roll bar thereby electrifying the inner surface of the Jeep. The driver is in contact with the inner surface. This is a list, from one year from one utility company, of people that died from contact with power lines. You will see that tires exploded from the contact and some caught fire. http://www.sigalarminc.com/HistoricalNotes.htm.
Factual error: Brown and Stokes mix up enough ballistics gel to make a life-size dummy to test their theory. The entire production (getting a mannequin, making a mold from the mannequin, etc,.) takes place in one shift. Ballistics gel needs to cool in a fridge, or on ice, (32-41°F) overnight. That alone eliminates the possibility that it was done in one shift. http://www.recguns.com/Sources/XD3.html.
Character mistake: Catherine Dent's character, Kay Marquette, plays the Holmes character Irene Adler with an English accent. Adler was an American, as mentioned by Watson in "A Scandal in Bohemia".
Revealing mistake: When Warrick takes out the contents of the wallet, he removes a few 100 dollar bills. If you look carefully, you can see on the top bill it says "For Motion Picture Use Only."
Character mistake: When Catherine is being questioned about the victim, it is mentioned that her parents were killed in an industrial accident in Odessa. To which Catherine replies, "Russia?", and is answered in the affirmative. Odessa is a major city in the Ukraine, not Russia.
Continuity mistake: In the scene where the CSIs are first crawling into the nursery, you can see Grissom's ungloved hand, which was gloved before entering and after exiting the crawlspace. (00:19:00)
Continuity mistake: When Sara and Jim Brass are interrogating Tonya you can see Jim open up her cell phone behind Tonya. Than they do a wide shot and Jim opens up the phone again.
Big Middle - S5-E16
Continuity mistake: The board behind the oddsmaker keeps changing. At the beginning, he has crossed out the odds on the game between Miami and Memphis from 5 to 7 1/2 to 10 1/2. When Brass comes in, the board is only showing 5. It then changes every time it switches from Brass to the oddsmaker- it will show the 5 crossed out and then not crossed out the next time. Finally in the final shot, it shows the board without the 1/2 after the 10. (00:17:15)
Big Middle - S5-E16
Continuity mistake: Season 5 Episode 16 "Big Middle" Sara Sidle marks a triangle on a bed sheet around evidence and then proceeds to cut along the inside of the triangle lines in order to remove the evidence from the sheet. In the next shot, Sara is shown removing the cut out from the sheet, which now has been cut along the outside of the triangle lines.
Revealing mistake: Season 5 Episode 18 "Spark of Life": when they show a closeup of the badly-burned woman during her debridement, it can be seen that even though her eyebrows and hair and, in fact, 90% of her skin has been burned away, she still has long, full eyelashes.
Factual error: Sanders is seen in the burn victim's OR, during debridement, wearing his street clothes (under a paper apron), and no mask or hat. Considering that the woman's skin is practically one continuous open wound, and her immune system is in an exceedingly fragile state, there's no way a breach of sterility like that would be allowed.
Other mistake: Episode 18 Season 5 "Spark of Life": Late in this episode, the CSI crew is sitting around discussing the case. Sarah Sidle summarizes the facts in the case, including making the comment that Tara Matthews was attacked by the truck driver "just before her death"; in actuality, while Tara was severely burned, she remained alive in the hospital throughout the entire episode.
Revealing mistake: Season 5 Episode 4X4. When Warrick and the young coroner are examining the dead woman in the RV, look closely as you can see her blink.
Continuity mistake: The Pontiac Fiero that is seen underneath the Hummer is a different (but newer) model than the one that was briefly seen driving away from the taco stand.
Revealing mistake: Willows discloses a laptop with the city's grid layout inside the welder's truck, and grabs her cell to call Grissom. Just as she presses last number, he immediately answers, without so much even a ring.
Answer: He doesn't have the authority to arrest him - when anyone is arrested in the show, a police officer does it. Also he tells Ty that he is going to be submitting his case findings to Ty's insurance company, who would no doubt contact the IRS, who then would have him arrested for fraud etc.