Factual error: The murderer kills the two students by drilling a hole through the adjoining wall of the victim's room at floor level, placing 40lbs of dry ice next to the hole, and allowing the sublimating carbon dioxide to pass through the hole into the victim's room and creating a toxic atmosphere. Since the two rooms are at the same air pressure, the only possible way for the CO2 to move from one room to the next is to be pumped through. As neither room has an excessive level of carbon dioxide in the atmosphere the sublimating gas would fill both rooms until the CO2 levels in both rooms was the same.
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.
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.
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.
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.
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.
Continuity mistake: When Grissom is on top of the box, talking to Nick, and he tells Nick to put their hands together, you can see that from shot to shot, the alignment of their hands changes. In one shot (from Nick's angle), Grissom's hand is higher than Nick's, as well as Grissom's index finger lines up with Nick's middle finger. In the next shot, their hands line up perfectly. The alignment changes throughout those few shots.
Continuity mistake: There are some major continuity errors in the rescue scene at the end: First, the loader is missing from the side of the grave during several of the shots. Second, the rope changes position. The CSI crew is shown manning the rope, which is running parallel to the ground, ready to pull Stokes out of the grave. (There is a physics problem with this anyway.) The next shot is a close up of Grissom and Brown and the rope is now going up at a severe angle. Brown can barely reach it. (The stuntman can only be pulled out from above, the aforementioned physics problem, and the rope is leading up to the rigging.) Third, immediately after the stuntman is pulled from the grave and right before the explosion, there is no one and nothing near the grave. The loader ends the scene right where it started: on the edge of the grave, bucket up, lights on.
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 "Grave Danger" (parts 1 and 2); there are a number of shots of Nick in the grave which don't match what the CSI team see via webcam. For example when he is speaking into the tape recorder he is holding it above his head from the view inside the grave, but from webcam he is holding it further down.
Other mistake: There is no way a body can be pulled out of a grave the way they showed. It would be a pretty tough trick to pull off with a 6', 200lb piece of lumber and virtually impossible with a body. If it was a solid, non-flexible piece of material, pulling on the rope would drag the item until it hit a ledge and then flip it out of the grave. The body is very flexible, especially at the waist. You'd have to pull a body from above, which they end up doing in real life.