(at around 12 mins) When discussing the bounties over the Russian and FBI officers, Koslova says that the city of Porvoo is 60 kilometers west from Helsinki. In reality, Porvoo is about 50 kilometers northeast of Helsinki.
(at around 15 mins) When Sophie gives the passports to the Jackal she says that ethyl acetone causes liver cancer. Ethyl acetone is a popular solvent and one of the primary reason is that it is non-toxic.
(at around 1h 45 mins) When Declan is shooting a Sig-Sauer pistol at the Jackal, he imitates the recoil as blank guns don't have recoil. Except his imitation is late, recoiling after the gun is fired, which would be wrong, as the recoil is simultaneous to the firing of the gun.
(at around 1h 40 mins) When Declan and the marine sniper are looking at the van, the latter says it is at 762 meters away, when it is clearly much closer. 762 meters are exactly 2500 feet. Perhaps they meant 76.2 meters.
(at around 59 mins) When the Jackal is doing "speed test" and chasing running Lamont with his gun remote control, the display shows range 38-40 meters at the moment when Lamont slips and falls into slop and even later when he's beside the target car. However, the camera view high above the shooting scene reveals that the target car is at least twice that far.
(at around 1h 8 mins) When the FBI agents are at the marina waiting on the end of the boat race, Koslova lights her cigarette. In the next shot, she is holding it between her fingers and it is lit. When we next see her, she is lighting her cigarette again.
(at around 1h) When the Jackal is aiming at the pack of cigarettes Lamont is holding in his hand, he actually shoots Lamont's forearm between hand and elbow, where a cloud of blood can be seen. On subsequent shots, the arm is chopped off just below the shoulder.
(at around 1h 45 mins) The scenes in the subway supposedly take place first in the Capitol Heights metro station, then in the "next station," Metro Center, to which the Jackal runs. In reality, 10 stops and over six miles separate the two stations.
When running into the train station, a large sign reads "SUBWAY" above an entrance to Capitol Heights Metro Station. In Washington, D.C., the train system is only referred to in signage and locally as Metro.
(at around 57 mins) The heavy machine gun used by the Jackal (Bruce Willis) would recoil so violently that the consumer grade camera lens shown mounted on it (a Cannon telephoto lens) would shatter after the first time it was fired. As a rule, only optical devices that are designed for use on firearms would survive the forces involved in the operation of the weapon.
(at around 1h 40 mins) The 14.5mm canon used by the Jackal (Bruce Willis), produces a shock wave that would shatter that glass in the minivan in which it's mounted. Furthermore, the recoil of the weapon would move the minivan so violently that after the first few rounds fired, the weapon would no longer be accurately aimed at the target.
(at around 57 mins) When we see the weapon is first test fired from the mount and misses, the problem is unlikely to have been with the mount and more likely to be poor alignment of the sighting system.
(at around 18 mins) Canadian Postal Code for The Jackal's Montreal delivery address is in an incorrect format. The correct format is letter-number-letter number-letter-number (e.g., A1B 2C3). The postal code in the movie was letter-letter-letter number-number-number (e.g., ABC 123).
(at around 59 mins) When the Jackal is test firing the weapon, he only fires one shot. Then he tells Lamont to 'Run' and the Jackal tracks him with the camera. On the screen as Lamont starts running you can see the readout shows 2 shots fired, and not one.
(at around 1h 30 mins) The Jackal is wearing a long sleeve uniform shirt in his impersonation of a DC policeman when all the other DC police officers are wearing short sleeve shirts which would be the required uniform to be worn specific to a certain time-frame of the year.
When Jackal is watching television program about hyenas while in Finland, there is no Finnish subtitles in program. All the foreign programs broadcast by YLE (national public service broadcasting company) were subtitled with hard-coded subtitles in Finland.
Near the beginning of the movie, when The Jackal orders a weapon to be delivered to an address in Montreal, the postal code he provides starts with a G. All postal codes in the city of Montreal start with an H.
The Jackal sails from Canada to the US with the gun hidden inside the boom of his yacht, which he then moors very publicly. He is then recognised and escapes, but it is never explained how he manages to retrieve the gun.
(at around 17 mins) When ordering the weapon from the speaking computer, the Jackal claims he would prefer non-American equipment; however, later on in the movie (at around 55 mins) he tells Jack Black's character that the ammunition is depleted uranium, which is only used by US forces.
(at around 1h 7 mins) In the sailboat race to Chicago, where the Jackal is trying to blend in, the American flag is flying off the stern of the sailboat. When racing, only racing fleet pennants are flown. Any other flag indicates "I am not racing". The coastguard who waved to the Jackal would have realized this.
(at around 1h 40 mins) While the Jackal's weapon is mounted on a van and firing, we can see a part of the vehicle in one shot as the sniper shoots at the gas tank. The vehicle is not even shaking, which would surely be the case in reality. It's supposed to be a rapid firing 14.5mm cannon.
(at around 1h 50 mins) In the Metro tunnel the signal that Declan holds onto while the trains pass by remains green even after they are gone. A green signal should turn to red as soon as a train passes by.
(at around 1h 5 mins) When the Jackal is sailing, we see a helicopter shot of him setting the spinnaker - a sail that only works when the wind is from behind the boat. Then we cut to a shot of him sitting at the back of the boat, with the wind in his face (as can be seen from his hair, and the flag behind him).
(at around 1h 45 mins) After the final assassination attempt as the Jackal enters the Subway he swipes his subway pass into the automatic ticket gate. The magnetic strip is upside down and the card reader in the gate shouldn't be able to read it.
(at around 1h 26 mins) When Major Koslova is shot by the Jackal, he rubs a heart onto her left cheek with her own blood. Later when Declan is comforting her in her death throes, she has not a trace of the bloody 'valentine'. If the paramedics were trying to save her life they wouldn't waste their time cleaning her face.
The Jackal's final disguise is as a Policeman in uniform, complete with body armor under his uniform shirt. As he escapes he puts a windbreaker over the shirt and subsequently the body armor. Later he is shot with a handgun in the chest several times and bleeds from each chest wound. The body armor would have stopped those rounds.