Revealing mistake: When it starts hailing inside the cabin, you can obviously tell that the night sky has wrinkles in it, revealing that this "sky" is a black curtain in a stage.
Continuity mistake: When the cabin was struck by the boulder it was tilted downwards making Steve and Mike fall out the front window and door. As Steve and Mike were leaving to go watch the debate at Drake's bus, both guys walked uphill to leave by the front door.
Revealing mistake: At the very end of the film, when Chris Farley is stuck to the airplane when it's in the air, you can easily notice that he has been replaced with a dummy. You can easily tell by seeing his legs are too flexible and skinny.
Continuity mistake: When Drake sneaks up on Steve while he is urinating on the tree, he turns Steve around, and as happens in many films when someone is interrupted while urinating, his genitals are magically back in his pants. You can then hear Steve urinate on the ground a couple times as Drake continues to intimidate him, which wouldn't be possible if his genitals were back in his pants.
Revealing mistake: Could the scene when the big rock knocks down the cabin be any faker? You can easily tell that the cabin and the rock are miniature models.
Character mistake: At Governor Tracy's acceptance speech, she thanks her husband, Dennis, and two children, Andrew and Patrick. However, she has a son and daughter, not two sons. Additionally, her husband is credited as "Donald" not Dennis, who was played by Patrick Pankhurst.
Other mistake: The article on the right-hand side of "The Olympian" seen at the end of the film is the same one seen on the right hand side of the "Daily Journal of Commerce" that Tracy looks at after chopping down the tree. Although the 2nd column of print in the "Daily Journal of Commerce" is now the 1st column of print in "The Olympian."
Continuity mistake: When Mike and Al are on the football field talking, after the truck incident, they're a couple feet away from the "50" and start walking back to the cars, away from the "50" and get to about the 44-yd line. After Roger honks the horn, Mike and Al are now back to around the 50-yd line and next to the "50." And they're closer to the "50" then the first shot.
Continuity mistake: When Mike is talking about seeing his brother while Steve is asleep, you see the Playpen magazine sticking out from under his pillow, on top of a 2nd magazine. When Mike approaches him, the Playpen magazine is under the covers next to Steve and there's only one magazine under the pillow.
Other mistake: When we see the front page picture of Mike with the alcohol and joint, he's pouring the alcohol over his bottom lip and chin, going down the front of his shirt. This doesn't match what we see him do. It does appear that Mike spilt alcohol on himself when off camera, but the wet spot is on the right side of his jacket, but not down the front.
Audio problem: The last scene begins with Al and Mike walking towards the plane speaking. Al asks "are you sure you don't want a job on my staff?" Mike then responds by stating; "you know what Al... I don't really think I'm cut out for politics." Al then is heard laughing at this. It is very clear the audio laugh is actually that of actor David Spade and appears to be placed over a most likely silent smile of Al. (01:20:00)
Answer: A major police department would probably not allow modifications to an official vehicle, even if it was assigned permanently to a particular officer, due to safety or insurance concerns. That said, many departments do use high performance or exotic vehicles seized during crimes under various forfeiture laws. Most times these are for promotional purposes, but I do know of a Florida department that used a souped-up Dodge Hemi-Charger painted in standard department livery for traffic enforcement.