The subtitles give inconsistent spellings of Chinatown, sometimes as one word, sometimes as two words (i.e. "China Town").
In the game, the LCPD police cars are black and white. They were supposed to be blue to represent the NYPD's older styled vehicles, but because the game was released shortly after the September 11th attacks, Rockstar canceled the blue paint scheme and made them black and white.
When the character has a handgun, notice that one magazine is nine rounds, in reality police officers have handguns that usually hold 10 - 15 rounds per clip.
When the character enters the FBI car, notice that the car's name is poorly spelled "fbi car" when it should be "FBI Kuruma" (the civilian vehicle the "fbi car" is based on) or at least "FBI Car".
When the character reloads a handgun, notice that all he does is pull the chamber back, not correctly put a new magazine in the holder and then pull the chamber back.
When you get into a police car you receive a shotgun. The gun is strangely a Remington "Folding Stock" Shotgun, in reality police officers carry a 12 Gauge Shotgun in their cars and have the ammo separated from the gun, not already loaded.
When the player has a wanted star and is being chased by a police officer on foot, the player can escape by climbing into a car, closing the door behind them and driving away. However, the police officer can open the player's door while the player starts driving; rather than reacting to the vehicle in motion, the officer literally stands in place and opens the door as though the car was perfectly still.
During the Joey mission where you ram the armored car, the subtitles misspell "payroll" as "pay role".
Even after you beat a payphone mission, the payphone will still ring.
During the mission where you have to deliver the girls to the policeman's ball, the sign on the building advertising it is misspelled, reading "DEPARTMENTS" instead of "DEPARTMENT'S".
"Saint Marks" is misspelled on the road signs; it is missing an apostrophe after the "K".
Although of insignificance, during the police convoy scene, it is clear that there are at least 4 police officers in total. (At least one driver in the police cruiser and one driver of the van with two officers in the back on the van.) Once the fictional "patriot" SUV stops the police cruiser, only two officers exit their vehicles. The driver of the police cruiser and the police van, although animated, did not make an attempt aid their fellow officers or to continue driving forward. This is very strange, although this realism would strongly tamper with the actual introduction. Furthermore, if you look inside the Patriot when it swerves in front of the police cruiser there's no one actually driving it, this is true for the white Rumpo van that the two Colombians emerge from.
Checker Taxi Model A-style taxis are still being driven in 2001, when they were mostly retired by that point.
The military soldiers are wearing OD green uniforms, when they should be wearing M81 woodland camouflage instead.
The military soldiers are shown using fully-automatic M16 rifles, when they should be using three-round burst ones instead as fully-automatic M16s were largely replaced during the 1990s.
In the mission "Under Surveillance", Asuka's dialogue doesn't match the subtitles in every other version except PS2. The script was changed to the FBI and the subtitles don't reflect this. In the mobile version, the Mafia subtitles were changed to the FBI, but the other lines still don't match.
When you meet Donald Love for the first time, he gets off the treadmill but you still hear his footsteps running on it.
At the ending cutscene, the reporter says gunfire but the subtitles say "ground fire".
"Harbor" on the road signs is spelled the UK way, "Harbour".
All the directional road signs are blue; in the U.S. they are green.
In the game, Staunton Island is supposed to represent Manhattan from New York but strangely the city's skyscrapers strongly represent Chicago.
Liberty City is on the U.S. east coast therefore KJAH's radio station call sign should be WJAH.
The LCPD contact you meet in the park uses the term "car park", which is a UK term. The US equivalent is "parking lot".
Whenever a gang member attacks the player or a random NPC and the police are nearby, the police cars and officers won't react or go after them. Instead, the police will only go after the player even when they retaliate to a gang member attack. The only time the police reacts to an NPC attack is when they are caught in the crossfire.
During the cut-scene for the mission "Cipriani's Chauffeur", Michael Madsen, the voice actor of Toni Cipriani, mispronounces Toni's last name as "Kipriani".