When Riley is down in the Archives-Navy Memorial Metro stop to tap
the security system, the shot that he records of the preservation room shows the Declaration already there and covered, as Ben later finds it. However, Riley has not yet set off the temperature sensors, thus the document has not been taken down to the Preservation Room yet.
The length (and even existence) of Riley's goatee varies throughout the movie.
When Sadusky and his men are arresting Ben, the back of Riley and Abigail's heads can be seen leaving the scene, and a moment later, they can be seen turning away from them, waiting for their cue over Sadusky's shoulder. However, a moment later they come around the corner and witness Ben's arrest and then turn and leave again, for the third time total.
Young Ben Gates has brown eyes while the adult Ben Gates has blue eyes.
When Ian kidnaps Abigail after the Declaration is stolen, Ian asks her, "and just who might you be?" In that shot, his hair is completely dry. In the very next shot of Ian, not more than five seconds later, his hair looks to be soaked in sweat or water with the rest of him appearing to be dry.
Abigail collects George Washington's campaign buttons. In reality, William McKinley was the first president to use buttons to advertise his campaign. Therefore, Washington would not have had them.
Lemon juice is used to create invisible ink, not expose it, and it turns brown when heated; it does not fade away again as it cools.
The first Trinity Church burned to the ground when the British set the Great Fire of New York in 1776. The church was not rebuilt until the late 1780s.
When the characters go underground, Ben pulls a torch off of the wall and lights it, and it burns instantly and brightly. Also when the heroes find the treasure room, a river of fire is lit. There is no substance the 18th century colonials would have had access to which could have both produced instant flames of that kind and had its potency last for 200+ years.
When Ian and his henchmen are attempting to steal the Declaration of Independence, one of his men shots a security guard with a Taser. The security guard is then seen unconscious. Being shocked by a Taser does not render a person unconscious. Once the shock cycle is over, there are actually little side effects from a Taser.
Early on, when Ben talks about the Iron Pen, he states that fifty-five men signed the Declaration of Independence, when, in fact, fifty-six men signed it. One signature was not added until 1781; the clue was written before then. The writers were going to explain this, but decided this information was unnecessary for the story, so it was left out.
Ben borrows a $100 bill from a cashier to read the clock on the tower of Independence Hall on the reverse side of the bill. Ben says the time reads 2:22, but on current notes the clock reads 10:30. However, on the design on the reverse of Series 1990 $100 bills, the time on the clock is different and does actually show 2:22.
The film mentions many times that the Freemasons were trying to hide the treasure from the British, but Britain was where Freemasonary originally came from, and where it was still based at the time. However, prior to the American Revolution, colonial Freemasonry had begun to move away from its connections with British masonry, rejecting, for example, the need of the London Grand Lodge to approve new lodges. This trend accelerated during the Revolution as ties of Masonic brotherhood proved more fragile than temporal political allegiances.
The story unfolds, saying that Charles Carroll, a signer of the Declaration of Independence, gave a young Gates an important clue to treasure. The narration identifies him as a Mason. Some say this is not plausible because Carroll was a Roman Catholic, and being a Mason would have gotten him excommunicated. Although the family was strong Roman Catholic, Schultz in his History of Freemasonry in Maryland states that Charles was a Freemason in a Maryland Lodge. Daniel Carroll, cousin of Charles Carroll of Carrollton was definitely a Mason. There are, even today, many Catholics who are also Freemasons.
When they are investigating the wreck of the Charlotte, Ben seems to call Sean Bean's character Ian "Sean", but he is actually saying "Shaw," the name of David Dayan Fisher's character.
After crawling through the "creepy, crawly" space where the coffin was removed, all characters emerged without a speck of dust, dirt or cobwebs on their clothing. The knees on their pants should have been filthy.
When what is supposed to be the original Declaration is shown the "corrected" modern day version is shown instead. In 1776 the common calligraphic way of writing the letter "s" was to make it like an elongated slanted "f", so that the word Congress printed at the top would like more like "Congreff". Because this is confusing to modern day people, reproductions usually have it printed as Congress. Pictures of the authentic document show the old style of writing.
The Charlotte is completely buried in the ice and snow, yet when it is shown about 1/3 uncovered there are no piles of ice or snow anywhere around it and the ship now appears to be simply sticking up out of the ice plain.
When Riley and Abigail were in Philadelphia and just lost the Declaration, they were outside somewhere discussing what to do, and Abigail clearly has a wig on.
When the driver's side van window is shot, the auto glass shatters, making a large hole but leaving most of the glass shards in place. Once shattered, the glass pieces are very delicate and would fall at the slightest movement. But the pieces remain in place during the chase and during the shock of landing when the van goes airborne.
Ben, Abigail and Riley follow a clue from the engraving of Independence Hall on the $100 bill. Noting the time on the clock in the tower and following the shadow of the tower to a spot on a wall. In reality the original tower of Independence Hall that existed in 1776 had no clock, it was built only to hold a bell (i.e. the Liberty Bell). Furthermore, that tower became unstable and was removed in 1781 and was replaced by a simple peaked roof. The original clock on the building was built into the side of the building facing Congress Hall. The current tower with its clock wasn't built until 1828.
When Ian reads the clue from the Charlotte pipe, he concludes that "Silence" must be a proper noun, because it is capitalized. At the time (as can be seen in the Dogoode letters) any noun could be capitalized, regardless of whether they were proper nouns or not.
As the scaffolding is falling, nails are popping out. These are clearly manufactured nails and not cut nails of the type used in the colonial period. Also, the nails are of a silver color, while nails of the colonial period would have a black iron color.
When Abigail and Riley notice two of Ian's thugs chasing them, Riley says, "Time to run", but his lips do not move.
When the FBI agents enter his father's home (finding his father tied up), the agents enter through the front door, presenting handguns. A click is heard like a safety being released on a pistol. They're carrying Glocks. There is no external safety release on a Glock.
In the tunnels below the church, Patrick Gates appears to be lit from the torch he is holding. When he turns toward the camera, a square diffused light is reflected in his glasses and is the source of the "torch" light.
When Ben visits his father after stealing the Declaration and they argue, there are reflections of video screens in his father's glasses.
When Abigail and Riley are being chased from Independence Hall, one of the bad guys radios in to say they are on "5th & Chestnut". A second later, they are running into Reading Terminal Market which is at least 10 blocks away. Then they run out of Reading Terminal Market, and right into City Hall. That's about 5 blocks. So, basically they ran about a mile in 2 minutes.
When Riley goes down into the Archives-Navy Memorial Metro stop to
tap the security system, the train passing behind him is clearly a New York subway train and not a DC Metro train.
After Ben and Riley leave the National Archives, they are next seen on the steps of the Lincoln Memorial continuing their conversation. The Lincoln Memorial is at least two miles from the National Archives, and at least one mile from any subway station. It seems very unlikely that they would have had no substantial conversation on the long walk.
In the shot outside of the Franklin Institute, when the boy is retrieving the clues for Riley, a SEPTA bus passes by. The bus is the '108 Airport' bus. SEPTA route 108 runs no where near the Franklin Institute. It is a mostly suburban route.
The first shots of the group once inside Trinity Church reveal that they are actually inside the First Congregational Church in Los Angeles, California, USA. The pipe organ in the background does not match the one inside Trinity church.
When Ben hands Abigail the champagne flute, Riley asks if that's the hot girl. But Riley clearly knows the whole plan that he helped Ben prepare for, so he not only knows her name, but also that she was Ben's only target in going to the gala. And he has had a conversation with her, so he knows her voice.
On the phone, Ian says to Ben "I know about the glasses." He couldn't have known that they existed. Neither he nor his henchmen ever saw the glasses being found, used or carried by anyone.
When Ben is holding the Declaration inside of Independence Hall, he reverently states that "the last time this document was here it was being signed." That is incorrect. In 1876, in celebration of the 100th anniversary of the Declaration and of the nation, President Ulysses S Grant had the DOI transferred up to the 1876 Centennial Exposition in Philadelphia where it was on display for several months in Independence Hall. In fact, Pennsylvania politicians tried to keep it permanently but they lost that bid. The only other time since then that it left Washington DC was during World War II when it was secured at Fort Knox, Kentucky.
Abigail's password into the preservation room is supposed to be
VALLEYFORGE, an eleven letter password. When she enters her password, she only types eight characters, one being an N and one being the space bar, neither of which are found in VALLEYFORGE.
When Ben is hiding from Abigail in the gift shop, he ends up buying a Declaration replica using his credit card. Throughout this scene, Riley is known to be listening in to Ben's conversations, so he would have heard at least Ben's side of that transaction. Yet later when discussing their options in the park, Riley expresses surprise about the credit card transaction.
When Riley has to start the van during the getaway from the National Archives, he slams his feet down on the brake and the accelerator at the same time.
Riley wears glasses to see things up close, such as when he's writing down the letters that the Institute Kid gives him. He looks up to see the advertisement of the bank on the side of the bus, and sees the picture of the Liberty Bell clearly... but because he's still wearing his glasses, the picture on the bus would have been a blur, and he wouldn't be able to read it.