Naoto Tamura/Mobile Cop Jiban is the main protagonist of Kidou Keiji Jiban. He is a human who was fatally injured in an attack by Bioron and rebuilt as a cyborg by Doctor Igarashi to fight Bioron. He is capable of reverting to his human identity at will. He holds the rank of police commissioner (as a robot) and detective (as human). Jiban's programming enables him to follow these directives:
- Arrest criminals in any circumstance without a warrant.
- Punish criminals on his own judgment if they happen to be members of Bioron.
- Use lethal force depending on the circumstances.
In human form, Naoto often plays the fool and is looked on down by Youko and Kiyoshirou for this, but Youko begins to warm up to him after realizing he could be Jiban.
It can be used as a communicator to contact Harry Boy, Seiichi and Mayumi in Jiban's Base or used to summon any of his vehicles, as well as to control their armaments electronically.
- (1st Article) Mobile Cop Jiban, under any circumstances, can arrest the criminal without a warrant.
- (2nd Article) Mobile Cop Jiban, in case the enemy is recognized as Biolon, can apply the punishment by his own judgement.
- (Attachment) Depending on the circumstances, even erasing him is allowed.
- (3rd Article) Mobile Cop Jiban's maximum priority is human life, and every given order that disregards this can be rejected.
- (5th Article) In the case of Biolon manipulating the humans' heart, the punishment can be applied by his own judgement.
- (6th Article) The crime of disposing of children's dreams, and hurting their heart is especially severe.
- (9th Article) Mobile Cop Jiban can erase everyone that destroys all lifeforms' peace by his own judgment.
Super Police Vehicles
- Super Police Machine Reson: Jiban's patrol car, a modified Pontiac Firebird with a sixth generation computer and hence a will of its own, and it was destroyed by Gibanoid.
- Super Police Bike Vaican: Jiban's Suzuki motorcycle with a sixth generation computer and hence lasa will of its own, and it was destroyed by Gibanoid.
- Super Police Jet Spy: Jiban's stealth fighter plane with a will of its own, and it was destroyed by Doctor Giba using his ship's weapon systems.
- Spikes: It is hidden in Jiban's upper arms to puncture and break a hold or to shoot.
- Jiban Hip Beam: It is hidden in Jiban's upper arms to shoot into areas that cannot be accessed through physical means (example: doors). Jiban used it in the movie.
- Maximillion Type 3: Jiban's personal jutte-like weapon. Concealed in a collapsible holster located on his right leg, it can transform into either Pistol, Stun Gun, or Sword Mode. The Maximillian Type 3 can also perform the following moves and techniques:
- Disclose Shock: It is used in stun gun mode, essentially a stun gun.
- Last Shooting/Search Buster: It is used in pistol mode, firing laser shots.
- Jiban End (Energy Sword): It is used in sword mode, splits enemies in half.
- Daedalus: Jiban's personal cannon. Required to perform the Daedalus Bombard Technique, which is used to finish off foes. It can be made into a Jetpack jet to enable Jiban to fly short distances.
- Autoderringer: Jiban's personal rifle. He acquired it after being resurrected as Perfect Jiban. It has a machine gun mode and a bazooka mode. The machine gun mode is used to stun and set up the enemy; after an "Energy Charge" in which the bazooka is charged, it fires a powerful shot to finish off the enemy. It was destroyed by Gibanoid during Jiban's final fight with him.
- Powerbreaker: A left arm attachment. It can be used to attack enemies. He acquired it after being resurrected as Perfect Jiban.
- Needricker: A right arm attachment. It can be used to drill into areas that cannot be accessed through physical means (e.g. doors). Acquired it after being resurrected as Perfect Jiban.