Corrected entry: When interrogating the Uncle, the agents say that Emily is left handed (reinforced by when they throw a ball to the uncle and he catches it with his right hand). In a later scene, they show Emily drawing the black and white picture for the "unsub" with her right hand.
Corrected entry: Previous episodes of the series have established that the series takes place in present day, well into the 2000's. The models of cell phones and cars used, references to the 9/11 attacks, etc. In this episode, both Jacob and Sarah Jean are shown to be executed in the electric chair. The problem is; Florida has not used the electric chair for executions since July 8, 1999. Ever since, the state has used lethal injection for capital punishment.
Correction: Lethal injection is the primary method of execution in Florida, but inmates on Death Row do still have the option of choosing electrocution. In real life, none have since 1999, but it is still a legal and possible method in the state of Florida. No mistake here.
The Fisher King: Part 1 - S1-E22
Corrected entry: Reid mentions to Garcia that schizophrenia is genetic; this, however, has never been proven.
Correction: In fact the matter is a subject of intense debate and many scientists believe that it is genetic, and will unhesitatingly say so. That is the case here.
Correction: Schizophrenia tends to run in families, but no single gene is thought to be responsible. It's more likely that different combinations of genes make people more vulnerable to the condition. However, having these genes does not necessarily mean you'll develop schizophrenia. If one of your parents have schizophrenia then your chances are 6-10% of developing it.
Compulsion - S1-E2
Corrected entry: At the end of the show, Gideon and Reid are playing chess, and Reid says "check in three." Gideon then puts him in checkmate with one move. We have seen the board from all angles, and it is not possible for check in three or checkmate in one.
Correction: Watch the scene again. After Reid said "check in three", they literally show you the next four moves. The third move, Reid puts Gideon in check and the 4th move Gideon checkmates Reid. (When the camera cuts back to Gideon, the 4th move is already done and he's picking up Reid's captured Bishop).
The Fisher King: Part 1 - S1-E22
Corrected entry: We are told that an analysis of the DNA from the hair sample held in the evidence bag shows it came from Rebecca Bryant, the first victim of the serial killer they are hunting. Later we see a clear shot of the hair - it is a lock of hair, cleanly cut off, and tied with a ribbon. There are no roots, which are the only parts of the hair that contain DNA - hair shafts do not. They would not be able to harvest DNA from this hair sample.
Correction: That's true, but they probably would have cut off that part and used to to get the DNA, the roots are small and they probably would have had to use it all, but they would still keep the hair it came from as the evidence.
Compulsion - S1-E2
Corrected entry: When the professor gets killed, a kid is shown trying to drink out of the water fountain, but the water is turned off. Gideon figures out that there will be no water to the sprinklers, so a fire is soon going to be set. In real life, fire sprinklers are not connected to the main water supply. Sprinklers are on a separate pump. (00:15:00)
Correction: There are times when a building sprinkler system may be completely separate from the building water supply, but this isn't necessarily the case. The sprinkler system may tee off the water main. The interconnect valves would be secured and alarmed, but that wouldn't be impossible to circumvent.
Correction: If the building's water main has been shut off the will be no water to either sprinklers or water fountains. A "typical" building has only one water main.
Correction: The girl shown later drawing with the unsub is Jackie, the introverted daughter of the third family.