Factual error: At the end of the film, when Duchovny and Jones are on the ladder truck shooting the head and shoulders, they are yelling "go go go". They slide down the ladder and the next shot is the fire truck speeding away. Movie elapsed time 5 seconds. It is a physical impossibility for a fully extended ladder to be lowered, retracted and bedded in a span of less than 4-7 minutes. Even if the hydraulic lines are cut, the ladder would remain upright and not collapse/retract. (01:32:59)
Factual error: Cadence arrives for the wedding on a 727. Closer examination of the aircraft's livery reveals it is a Kitty Hawk Airlines aircraft. This would be fine were Cadence air freight, as Kitty Hawk is a cargo airline. (00:28:40)
Factual error: A minor only has a certain amount of time (typically, 6 months) to invalidate a contract entered into when such person was underage once that person turns 18 (or the age of emancipation in that state). This brings up a plot hole: If the marriage was not invalidated because Samantha Cole was underage, the prenuptial agreement would not be either, and Fletcher could not have used that argument to win the case, since he specifically states that she was seventeen at the time of her marriage.
Factual error: John Candy is at the top of the Calgary Tower having lunch. In the background you see a building called Bankers Hall which is slightly higher than the Calgary tower, that's fine except this was the 1988 Olympics, that building wasn't completed until late 1990.
Factual error: When the submarine rises in the waters of Norfolk and you see Norfolk in the background, there is one blatant problem. There are NO mountains in Norfolk. Most of Norfolk, Virginia, is below sea level.
Factual error: When Steve Martin dies with the mask on, the inflation bulbs (the little black bags that inflate and deflate) deflate completely. Actually they should INFLATE completely and stay that way. The gas is still on full blast and Steve is no longer inhaling (which would cause them to deflate). It was done only to emphasize Steve Martin's demise but it's factually incorrect.
Factual error: Early in the movie we see the newspaper dated "Sunday, March 14, 1987". March 14, 1987 was a Saturday, not a Sunday.
Factual error: Deer are not repelled by the smell of human urine, and in fact it does not have "a" smell - it has many. The smell of human urine varies enormously based upon diet, health and environmental factors so that no wild animal could possibly be scared of them all. Even if Lou didn't know this (and everything about her character suggests she should), Doctor Stone would - he is a doctor, after all.
Factual error: At the end of the movie, they show a bunch of ducks flying. Those are not ducks, they are geese.
Suggested correction: This was intentional. This is a mostly Minnesotan team and the team is going home. While geese are technically speaking not ducks, they are the state bird of Minnesota and fly in a very similar manner to ducks. This was meant to be a symbolism of them going home to their state.
Factual error: Dr. Dolittle is driving through San Francisco with a cup of Dunkin' Donuts coffee - there are no Dunkin' Donuts in San Francisco.
Factual error: The size of the shadow of an object depends upon its distance from the light source, not the surface it falls upon. Lifting the cutout of the bird a few inches closer to the sun as they do would make absolutely no difference to the size of its shadow, yet it quadruples in size.
Factual error: After Marisa is almost raped by those 2 guys, she wants to be driven to work. Her brother drops her off, but wouldn't give her the car because he had school the next day. But it was the day before Christmas Eve that night, and who has school on Christmas Eve?
Factual error: In 1999 when April is filming inside the research facility, you can see her video camera displaying Bluetooth, which wasn't available in cameras until 2002.
Factual error: In one scene, Mrs. Doubtfire pulls the symbol off of Stu's car. She shouldn't have been able to do that, since a cable connects the symbol to the inside of the car.
Factual error: There is a a scene showing round bales of hay and as anyone in this district would know we never had those shaped bales out here in Parkes when man first walked on the moon, we only had the old rectangle shape bales of hay.
Factual error: During the movie, Doug watches video from the previous Olympic competition. The skaters are shown performing in a darkened arena lit by spotlights. Special lighting effects like this are not allowed in competition. All competitions take place in a brightly lit arena.
Factual error: When Kharis is being examined by Petrie, he says that the lines on his face were caused by him being buried alive. In the next sentence he goes on to say that Kharis shows the best example of the embalmer's art that he has ever seen. Strange - if you're planning on burying someone alive you wouldn't embalm them first - that process would kill them!
Factual error: The baby is expanded to approximately fifty times his height, width and girth but it's explicitly stated that he retains his orginal mass. This means he will have the same volume as one hundred and twenty five thousand babies of his original size, but will weigh the same as before he was enlarged! That child is going to weigh much less than the volume of air he displaces. He's going to float away.
Factual error: Near the beginning of the film, Calico is sitting with a cat on his right shoulder. Their reflection is shown in the glasses of a man directly opposite. The reflection shows Calico and the cat in the same position instead of being reversed, as a reflection would be. (00:04:30)
Factual error: When Syd throws the pistol to detonate the landmine, nobody in the nearby vicinity seems to be injured except one 'bad guy' despite the fact that many modern anti-personnel mines project shrapnel to a radius of 30 meters. (02:17:35)