The National Office Of Security Enforcement (NOOSE) is an high-end law enforcement organization in Liberty City in Grand Theft Auto IV. It is a consolidation of the Military and SWAT units seen in previous GTA games.
NOOSE is based on the U.S. Department of Homeland Security and is separated into two divisions: the Liberty City Patriotism and Immigration Authority, based on the U.S. Customs and Border Protection, and the Liberty City Tactical Response Unit, based on the NYPD Emergency Service Unit.
NOOSE is called upon to assist the police when the player has a wanted level of at least 3 stars, before the FIB. Patriotism and Immigration Authority officers are largely similar to the LCPD's in behavior, weapons, appearance and mannerisms. Tactical Response officers, however, are designed to appear as fully equipped tactical squad units, with heavy armor and weaponry.
NOOSE's vehicle fleet consists of modified Police Cruisers, Patriots, Enforcers, Annihilators, and Armored Personnel Carriers. The NOOSE Cruisers and Patriots are exclusively driven by Patriotism and Immigration Authority officers, while the Enforcers and the APCs are used solely by the Tactical Response Unit. The Annihilator may appear with occupants from either division, depending on who is pursuing the player on the ground.
NOOSE are typically armed with Carbine Rifles, Pump Action Shotguns and SMGs. In The Ballad of Gay Tony, some NOOSE units are also armed with Assault SMGs and Automatic Shotguns. This weapon combination is very deadly; Carbine Rifles to take the player out at long range, Shotguns for short range and SMGs for medium range. If NOOSE agents have their weapons shot out of their hands, then they will pull out Pistols and continue to engage the player. NOOSE units are protected with Body Armor nearly doubling their endurance. In Grand Theft Auto: Chinatown Wars, NOOSE agents are equipped with Micro SMGs. In helicopters NOOSE units will fire on the player with Carbine Rifles. In The Ballad of Gay Tony however, they will use the Advanced MG instead. In The Ballad of Gay Tony missions Corner Kids and Not So Fast, they are also known to use Rocket Launchers.
- After the suspect is killed or arrested, NOOSE Officers will remain in the area combat readied for at least 5 minutes real-time. This is true to reality, as SWAT Officers and other law enforcements are trained to remain at crime scenes in case there is another potentially dangerous suspect.
- Tactical Response officers are well protected with body armor and don't lose health very quickly. Despite being more resilient to damage, Tactical Response officers are slightly less accurate than FIB Agents. Even with body armor, like all pedestrians, a single headshot instantly kills them.
- Agents always use good cover (e.g. behind a car, behind a wall, inside their helicopter).
- Tactical Response officers usually move together as a unit and pursue the player more aggressively than LCPD officers on foot.
- All Tactical units are always in a crouched position making it harder to get a headshot.
- Like the FIB, NOOSE Units will sometimes disappear off camera when the player has no wanted level.
- Even after the player has lost his or her wanted level, NOOSE Tactical Response Unit officers will remain in a crouched position, and will position their hands as if they were holding a gun, specifically a Carbine Rifle.
- NOOSE teams will also hide in unseen places to capture the suspect when he/she is off guard.
- A noose is a type of self-tightening knot, most commonly known for the Hangman's knot used in public hangings. A reference to the Hangman's knot is the one is depicted on the eagle's shield within the NOOSE seal.
- NOOSE's seal is a combination of the seals of the U.S. Department of Homeland Security and the National Security Agency. The primary design (color scheme, border, and eagle) is based on the DHS seal, while the shield and key the eagle is holding is similar to the NSA seal.
- The player may notice that the insignia of NOOSE on the NOOSE Cruiser and NOOSE Patriot is labeled LC Noose. After the capital "N," the following letters are all lowercase and the second "o" is smaller than a regular lowercase letter. This may be a reference to GTA III's FBI Car, which is poorly written as "Fbi Car".
- Although the APC in TBOGT bears "NOOSE Tactical Response Unit" labeling, it is never actually used by the NOOSE, apart from the mission Frosting on the Cake.
- If the player throws a grenade under or near a NOOSE Enforcer it will not even try to move away from that area, which the normal Police cars would do.