Continuity mistake: When Sara is riding up the school pathway on her moped,beside her you see a boy pulling his bike along approaching his friends and he is about half a meter away but in the next shot the boy with the bike is about two meters away from his friends. (00:17:05)
Continuity mistake: After Willie sees his partner's head in the washing machine, he panics and walks backwards. He trips over the dead body of his partner, he falls over his body and his arms are straightened out, but when you see him next his arms are straight against his waist and hips. (00:09:25)
Continuity mistake: When you see Freddy being interviewed you see Nora watching him on the TV, the camera is at a reverse angle and you see that her hand is somewhere round her face and her head tilts but in the very next shot,she doesn't have her hand near her face and also her head is completely still. (00:30:30)
Continuity mistake: In the scene after the fake skeleton breaks through the wall Donna puts her mahogany coloured top back on. In a few seconds she kneels down to pick up her camera equipment from the floor without anything with her, but seconds later, when she grabs her camera gear, she has the small camera attached to her ear. (00:53:15)
Continuity mistake: When Jenny is about to take her top off, in the close up you see that the shirt is lifted halfway up from her bra. In the very next shot when the camera is over Bill's shoulder, her shirt is only lifted a few centimeters below her bra. (00:39:30)
Continuity mistake: When we see Michael in the flashback with the security guard, he has on his mask from this movie, when it should be the Halloween H2O mask.
Continuity mistake: Jen's head lands at the bottom of the stairs. Later on in different scenes of the movie, it's obviously not there anymore because of all the running around downstairs and upstairs. Yet it's conveniently where it landed the first time because we see it on the monitor in the garage.
Continuity mistake: When Michael pins Rudy to the door, he uses the two knives that Rudy had in each hand. One of the knives goes clear through the door and out the other side. Michael then gets another knife from the drawer and it too goes through the other side, but the first knife that went through is now gone.
Continuity mistake: In wide shots of Deckard at his computer, the image on the monitor shows a basic white page with black and blue lettering. In close-up shots of the monitor, the image is much more detailed, showing a colorful college chat page. (00:20:35)
Continuity mistake: When the garage sets on fire Freddy bursts through the door and the camera angle is over Michael Myers' shoulder and he lowers his knife in his hand and then in the next shot when you see him staring at Freddy he lowers his knife again. (01:16:30)
Continuity mistake: After Charlie gets his neck impaled by the tripod leg he is dragged along the floor with his hands up to his neck and then they go above his head but next when you see Nora on the phone to Freddy the screen behind her has Charlie with his hands on his neck again. (00:29:15)
Continuity mistake: When all of the six are around the table lighting the candles, you can see Jen shine her torch up to her face, but in the next shot with the four way split screen, her torch is not lit. (00:37:25)
Continuity mistake: When Freddy pours the wine into the glasses with Nora, the screen behind him has a lantern held by Bill. Next, when Michael Myers breaks through the mirror Bill is struggling in agony, and in the next shot when you see the screen behind Freddy, the motions are the same as it was twenty seconds ago. (00:43:10)
Continuity mistake: The second after Jen gets her head sliced off you see her body is still standing but in the next shot when you see her head rolling down the stairs her body is laying flat on the landing. (01:01:15)
Continuity mistake: When Jen and Bill are walking up the stairs on their way to Judith Myers' room, Jen accidentally trips and breaks a step halfway up the stairs. After she says, 'Hands off,Bud,' she walks away from him about two steps, but in the next shot she is only three steps away from the top. (00:37:55)
Continuity mistake: When you see Donna, Jim and Rudy approaching the house to get ready you see that they are the only ones on that side of the house. You can tell because the wall is on their left side, but in the next shot you also see Bill on the same side. Where did he come from? (00:30:35)
Continuity mistake: After Willie trips over his beheaded partner his torch is in his left hand but after Michael Myers slices his throat and falls down his torch is in his right hand. (00:09:35)
Continuity mistake: When Deckard is at the party he goes up to the opening doors and tries to sneak in. Inside you can just see a lamp and a few bronze pots on the floor but when he enters the room you can see lots and lots of furniture and objects in the room. (00:36:15)
Continuity mistake: At the end when the garage is on fire Freddy shouts out, 'Happy F*****g Halloween', and when you see Michael caught up in the wires there are hardly any on his left side but when you see him from the camera there is a whole load of them surrounding him. (01:17:55)
Continuity mistake: When Michael Myers stabs the first two knives into Rudy and it goes through the door he gets the other one out of the drawer which is about three meters away but when he actually takes it out of the drawer and stabs it through him the drawer is like fifty centimeters away. (01:04:10)
Answer: At first impression, Laurie was catatonic not only from the shock of killing an innocent man, but also from a lifetime of being chased down by her murderous brother. She obviously knows from past experiences that nothing she does (including faking her own death) will stop Michael from finding her. It is later revealed she has been faking her mental issues (think when she has been hiding her regular meds in the raggedy Ann doll) and is committed only to stopping Michael, no matter what the cost. She may have also been trying to protect her son and the only way to do that is to allow herself to be institutionalized in order to lure Michael there.